Radio link failure reporting based on a failure of a beam failure recovery procedure

ABSTRACT

A wireless device initiates a beam failure recovery procedure based on a beam failure of at least one beam of a cell. A radio link failure is determined based on a failure of the beam failure recovery procedure. A radio link failure report is transmitted. The radio link failure report comprises: a first field indicating that the failure of the beam failure recovery procedure is a cause of the radio link failure; and a second field indicating a random access resource for the beam failure recovery procedure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent Ser. No. 16/277,062,filed Feb. 15, 2019, which claims the benefit of U.S. ProvisionalApplication No. 62/631,234, filed Feb. 15, 2018, which are herebyincorporated by reference in their entirety.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

Examples of several of the various embodiments of the present disclosureare described herein with reference to the drawings.

FIG. 1 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 2A is a diagram of an example user plane protocol stack as per anaspect of an embodiment of the present disclosure.

FIG. 2B is a diagram of an example control plane protocol stack as peran aspect of an embodiment of the present disclosure.

FIG. 3 is a diagram of an example wireless device and two base stationsas per an aspect of an embodiment of the present disclosure.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals as per an aspect of an embodiment of the presentdisclosure.

FIG. 5B is a diagram of an example downlink channel mapping and exampledownlink physical signals as per an aspect of an embodiment of thepresent disclosure.

FIG. 6 is a diagram depicting an example transmission time or receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure.

FIG. 7A and FIG. 7B are diagrams depicting example sets of OFDMsubcarriers as per an aspect of an embodiment of the present disclosure.

FIG. 8 is a diagram depicting example OFDM radio resources as per anaspect of an embodiment of the present disclosure.

FIG. 9A is a diagram depicting an example CSI-RS and/or SS blocktransmission in a multi-beam system.

FIG. 9B is a diagram depicting an example downlink beam managementprocedure as per an aspect of an embodiment of the present disclosure.

FIG. 10 is an example diagram of configured BWPs as per an aspect of anembodiment of the present disclosure.

FIG. 11A, and FIG. 11B are diagrams of an example multi connectivity asper an aspect of an embodiment of the present disclosure.

FIG. 12 is a diagram of an example random access procedure as per anaspect of an embodiment of the present disclosure.

FIG. 13 is a structure of example MAC entities as per an aspect of anembodiment of the present disclosure.

FIG. 14 is a diagram of an example RAN architecture as per an aspect ofan embodiment of the present disclosure.

FIG. 15 is a diagram of example RRC states as per an aspect of anembodiment of the present disclosure.

FIG. 16 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 17 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 18 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 19 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 20 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 21 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 22 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 23 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 24 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 25 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 26 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 27 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 28 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 29 is an example diagram of an aspect of an embodiment of thepresent disclosure.

FIG. 30 is an example diagram of an aspect of an embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Example embodiments of the present disclosure enable operation ofwireless communication systems. Embodiments of the technology disclosedherein may be employed in the technical field of multicarriercommunication systems. More particularly, the embodiments of thetechnology disclosed herein may relate to wireless communication systemsin multicarrier communication systems.

The following Acronyms are used throughout the present disclosure:

-   3GPP 3rd Generation Partnership Project-   5GC 5G Core Network-   ACK Acknowledgement-   AMF Access and Mobility Management Function-   ARQ Automatic Repeat Request-   AS Access Stratum-   ASIC Application-Specific Integrated Circuit-   BA Bandwidth Adaptation-   BCCH Broadcast Control Channel-   BCH Broadcast Channel-   BPSK Binary Phase Shift Keying-   BWP Bandwidth Part-   CA Carrier Aggregation-   CC Component Carrier-   CCCH Common Control CHannel-   CDMA Code Division Multiple Access-   CN Core Network-   CP Cyclic Prefix-   CP-OFDM Cyclic Prefix-Orthogonal Frequency Division Multiplex-   C-RNTI Cell-Radio Network Temporary Identifier-   CS Configured Scheduling-   CSI Channel State Information-   CSI-RS Channel State Information-Reference Signal-   CQI Channel Quality Indicator-   CSS Common Search Space-   CU Central Unit-   DC Dual Connectivity-   DCCH Dedicated Control Channel-   DCI Downlink Control Information-   DL Downlink-   DL-SCH Downlink Shared CHannel-   DM-RS DeModulation Reference Signal-   DRB Data Radio Bearer-   DRX Discontinuous Reception-   DTCH Dedicated Traffic Channel-   DU Distributed Unit-   EPC Evolved Packet Core-   E-UTRA Evolved UMTS Terrestrial Radio Access-   E-UTRAN Evolved-Universal Terrestrial Radio Access Network-   FDD Frequency Division Duplex-   FPGA Field Programmable Gate Arrays-   F1-C F1-Control plane-   F1-U F1-User plane-   gNB next generation Node B-   HARQ Hybrid Automatic Repeat reQuest-   HDL Hardware Description Languages-   IE Information Element-   IP Internet Protocol-   LCID Logical Channel Identifier-   LTE Long Term Evolution-   MAC Media Access Control-   MCG Master Cell Group-   MCS Modulation and Coding Scheme-   MeNB Master evolved Node B-   MIB Master Information Block-   MME Mobility Management Entity-   MN Master Node-   NACK Negative Acknowledgement-   NAS Non-Access Stratum-   NG CP Next Generation Control Plane-   NGC Next Generation Core-   NG-C NG-Control plane-   ng-eNB next generation evolved Node B-   NG-U NG-User plane-   NR New Radio-   NR MAC New Radio MAC-   NR PDCP New Radio PDCP-   NR PHY New Radio PHYsical-   NR RLC New Radio RLC-   NR RRC New Radio RRC-   NSSAI Network Slice Selection Assistance Information-   O&M Operation and Maintenance-   OFDM orthogonal Frequency Division Multiplexing-   PBCH Physical Broadcast CHannel-   PCC Primary Component Carrier-   PCCH Paging Control CHannel-   PCell Primary Cell-   PCH Paging CHannel-   PDCCH Physical Downlink Control CHannel-   PDCP Packet Data Convergence Protocol-   PDSCH Physical Downlink Shared CHannel-   PDU Protocol Data Unit-   PHICH Physical HARQ Indicator CHannel-   PHY PHYsical-   PLMN Public Land Mobile Network-   PMI Precoding Matrix Indicator-   PRACH Physical Random Access CHannel-   PRB Physical Resource Block-   PSCell Primary Secondary Cell-   PSS Primary Synchronization Signal-   pTAG primary Timing Advance Group-   PT-RS Phase Tracking Reference Signal-   PUCCH Physical Uplink Control CHannel-   PUSCH Physical Uplink Shared CHannel-   QAM Quadrature Amplitude Modulation-   QFI Quality of Service Indicator-   QoS Quality of Service-   QPSK Quadrature Phase Shift Keying-   RA Random Access-   RACH Random Access CHannel-   RAN Radio Access Network-   RAT Radio Access Technology-   RA-RNTI Random Access-Radio Network Temporary Identifier-   RB Resource Blocks-   RBG Resource Block Groups-   RI Rank indicator-   RLC Radio Link Control-   RRC Radio Resource Control-   RS Reference Signal-   RSRP Reference Signal Received Power-   SCC Secondary Component Carrier-   SCell Secondary Cell-   SCG Secondary Cell Group-   SC-FDMA Single Carrier-Frequency Division Multiple Access-   SDAP Service Data Adaptation Protocol-   SDU Service Data Unit-   SeNB Secondary evolved Node B-   SFN System Frame Number-   S-GW Serving GateWay-   SI System Information-   SIB System Information Block-   SMF Session Management Function-   SN Secondary Node-   SpCell Special Cell-   SRB Signaling Radio Bearer-   SRS Sounding Reference Signal-   SS Synchronization Signal-   SSS Secondary Synchronization Signal-   sTAG secondary Timing Advance Group-   TA Timing Advance-   TAG Timing Advance Group-   TAI Tracking Area Identifier-   TAT Time Alignment Timer-   TB Transport Block-   TC-RNTI Temporary Cell-Radio Network Temporary Identifier-   TDD Time Division Duplex-   TDMA Time Division Multiple Access-   TTI Transmission Time Interval-   UCI Uplink Control Information-   UE User Equipment-   UL Uplink-   UL-SCH Uplink Shared CHannel-   UPF User Plane Function-   UPGW User Plane Gateway-   VHDL VHSIC Hardware Description Language-   Xn-C Xn-Control plane-   Xn-U Xn-User plane

Example embodiments of the disclosure may be implemented using variousphysical layer modulation and transmission mechanisms. Exampletransmission mechanisms may include, but are not limited to: CodeDivision Multiple Access (CDMA), Orthogonal Frequency Division MultipleAccess (OFDMA), Time Division Multiple Access (TDMA), Wavelettechnologies, and/or the like. Hybrid transmission mechanisms such asTDMA/CDMA, and OFDM/CDMA may also be employed. Various modulationschemes may be applied for signal transmission in the physical layer.Examples of modulation schemes include, but are not limited to: phase,amplitude, code, a combination of these, and/or the like. An exampleradio transmission method may implement Quadrature Amplitude Modulation(QAM) using Binary Phase Shift Keying (BPSK), Quadrature Phase ShiftKeying (QPSK), 16-QAM, 64-QAM, 256-QAM, and/or the like. Physical radiotransmission may be enhanced by dynamically or semi-dynamically changingthe modulation and coding scheme depending on transmission requirementsand radio conditions.

FIG. 1 is an example Radio Access Network (RAN) architecture as per anaspect of an embodiment of the present disclosure. As illustrated inthis example, a RAN node may be a next generation Node B (gNB) (e.g.120A, 120B) providing New Radio (NR) user plane and control planeprotocol terminations towards a first wireless device (e.g. 110A). In anexample, a RAN node may be a next generation evolved Node B (ng-eNB)(e.g. 120C, 120D), providing Evolved UMTS Terrestrial Radio Access(E-UTRA) user plane and control plane protocol terminations towards asecond wireless device (e.g. 110B). The first wireless device maycommunicate with a gNB over a Uu interface. The second wireless devicemay communicate with a ng-eNB over a Uu interface.

A gNB or an ng-eNB may host functions such as radio resource managementand scheduling, IP header compression, encryption and integrityprotection of data, selection of Access and Mobility Management Function(AMF) at User Equipment (UE) attachment, routing of user plane andcontrol plane data, connection setup and release, scheduling andtransmission of paging messages (originated from the AMF), schedulingand transmission of system broadcast information (originated from theAMF or Operation and Maintenance (O&M)), measurement and measurementreporting configuration, transport level packet marking in the uplink,session management, support of network slicing, Quality of Service (QoS)flow management and mapping to data radio bearers, support of UEs inRRC_INACTIVE state, distribution function for Non-Access Stratum (NAS)messages, RAN sharing, dual connectivity or tight interworking betweenNR and E-UTRA.

In an example, one or more gNBs and/or one or more ng-eNBs may beinterconnected with each other by means of Xn interface. A gNB or anng-eNB may be connected by means of NG interfaces to 5G Core Network(5GC). In an example, 5GC may comprise one or more AMF/User PlanFunction (UPF) functions (e.g. 130A or 130B). A gNB or an ng-eNB may beconnected to a UPF by means of an NG-User plane (NG-U) interface. TheNG-U interface may provide delivery (e.g. non-guaranteed delivery) ofuser plane Protocol Data Units (PDUs) between a RAN node and the UPF. AgNB or an ng-eNB may be connected to an AMF by means of an NG-Controlplane (NG-C) interface. The NG-C interface may provide functions such asNG interface management, UE context management, UE mobility management,transport of NAS messages, paging, PDU session management, configurationtransfer or warning message transmission.

In an example, a UPF may host functions such as anchor point forintra-/inter-Radio Access Technology (RAT) mobility (when applicable),external PDU session point of interconnect to data network, packetrouting and forwarding, packet inspection and user plane part of policyrule enforcement, traffic usage reporting, uplink classifier to supportrouting traffic flows to a data network, branching point to supportmulti-homed PDU session, QoS handling for user plane, e.g. packetfiltering, gating, Uplink (UL)/Downlink (DL) rate enforcement, uplinktraffic verification (e.g. Service Data Flow (SDF) to QoS flow mapping),downlink packet buffering and/or downlink data notification triggering.

In an example, an AMF may host functions such as NAS signalingtermination, NAS signaling security, Access Stratum (AS) securitycontrol, inter Core Network (CN) node signaling for mobility between3^(rd) Generation Partnership Project (3GPP) access networks, idle modeUE reachability (e.g., control and execution of paging retransmission),registration area management, support of intra-system and inter-systemmobility, access authentication, access authorization including check ofroaming rights, mobility management control (subscription and policies),support of network slicing and/or Session Management Function (SMF)selection.

FIG. 2A is an example user plane protocol stack, where Service DataAdaptation Protocol (SDAP) (e.g. 211 and 221), Packet Data ConvergenceProtocol (PDCP) (e.g. 212 and 222), Radio Link Control (RLC) (e.g. 213and 223) and Media Access Control (MAC) (e.g. 214 and 224) sublayers andPhysical (PHY) (e.g. 215 and 225) layer may be terminated in wirelessdevice (e.g. 110) and gNB (e.g. 120) on the network side. In an example,a PHY layer provides transport services to higher layers (e.g. MAC, RRC,etc.). In an example, services and functions of a MAC sublayer maycomprise mapping between logical channels and transport channels,multiplexing/demultiplexing of MAC Service Data Units (SDUs) belongingto one or different logical channels into/from Transport Blocks (TBs)delivered to/from the PHY layer, scheduling information reporting, errorcorrection through Hybrid Automatic Repeat request (HARQ) (e.g. one HARQentity per carrier in case of Carrier Aggregation (CA)), priorityhandling between UEs by means of dynamic scheduling, priority handlingbetween logical channels of one UE by means of logical channelprioritization, and/or padding. A MAC entity may support one or multiplenumerologies and/or transmission timings. In an example, mappingrestrictions in a logical channel prioritization may control whichnumerology and/or transmission timing a logical channel may use. In anexample, an RLC sublayer may supports transparent mode (TM),unacknowledged mode (UM) and acknowledged mode (AM) transmission modes.The RLC configuration may be per logical channel with no dependency onnumerologies and/or Transmission Time Interval (TTI) durations. In anexample, Automatic Repeat Request (ARQ) may operate on any of thenumerologies and/or TTI durations the logical channel is configuredwith. In an example, services and functions of the PDCP layer for theuser plane may comprise sequence numbering, header compression anddecompression, transfer of user data, reordering and duplicatedetection, PDCP PDU routing (e.g. in case of split bearers),retransmission of PDCP SDUs, ciphering, deciphering and integrityprotection, PDCP SDU discard, PDCP re-establishment and data recoveryfor RLC AM, and/or duplication of PDCP PDUs. In an example, services andfunctions of SDAP may comprise mapping between a QoS flow and a dataradio bearer. In an example, services and functions of SDAP may comprisemapping Quality of Service Indicator (QFI) in DL and UL packets. In anexample, a protocol entity of SDAP may be configured for an individualPDU session.

FIG. 2B is an example control plane protocol stack where PDCP (e.g. 233and 242), RLC (e.g. 234 and 243) and MAC (e.g. 235 and 244) sublayersand PHY (e.g. 236 and 245) layer may be terminated in wireless device(e.g. 110) and gNB (e.g. 120) on a network side and perform service andfunctions described above. In an example, RRC (e.g. 232 and 241) may beterminated in a wireless device and a gNB on a network side. In anexample, services and functions of RRC may comprise broadcast of systeminformation related to AS and NAS, paging initiated by 5GC or RAN,establishment, maintenance and release of an RRC connection between theUE and RAN, security functions including key management, establishment,configuration, maintenance and release of Signaling Radio Bearers (SRBs)and Data Radio Bearers (DRBs), mobility functions, QoS managementfunctions, UE measurement reporting and control of the reporting,detection of and recovery from radio link failure, and/or NAS messagetransfer to/from NAS from/to a UE. In an example, NAS control protocol(e.g. 231 and 251) may be terminated in the wireless device and AMF(e.g. 130) on a network side and may perform functions such asauthentication, mobility management between a UE and a AMF for 3GPPaccess and non-3GPP access, and session management between a UE and aSMF for 3GPP access and non-3GPP access.

In an example, a base station may configure a plurality of logicalchannels for a wireless device. A logical channel in the plurality oflogical channels may correspond to a radio bearer and the radio bearermay be associated with a QoS requirement. In an example, a base stationmay configure a logical channel to be mapped to one or moreTTIs/numerologies in a plurality of TTIs/numerologies. The wirelessdevice may receive a Downlink Control Information (DCI) via PhysicalDownlink Control CHannel (PDCCH) indicating an uplink grant. In anexample, the uplink grant may be for a first TTI/numerology and mayindicate uplink resources for transmission of a transport block. Thebase station may configure each logical channel in the plurality oflogical channels with one or more parameters to be used by a logicalchannel prioritization procedure at the MAC layer of the wirelessdevice. The one or more parameters may comprise priority, prioritizedbit rate, etc. A logical channel in the plurality of logical channelsmay correspond to one or more buffers comprising data associated withthe logical channel. The logical channel prioritization procedure mayallocate the uplink resources to one or more first logical channels inthe plurality of logical channels and/or one or more MAC ControlElements (CEs). The one or more first logical channels may be mapped tothe first TTI/numerology. The MAC layer at the wireless device maymultiplex one or more MAC CEs and/or one or more MAC SDUs (e.g., logicalchannel) in a MAC PDU (e.g., transport block). In an example, the MACPDU may comprise a MAC header comprising a plurality of MAC sub-headers.A MAC sub-header in the plurality of MAC sub-headers may correspond to aMAC CE or a MAC SUD (logical channel) in the one or more MAC CEs and/orone or more MAC SDUs. In an example, a MAC CE or a logical channel maybe configured with a Logical Channel IDentifier (LCID). In an example,LCID for a logical channel or a MAC CE may be fixed/pre-configured. Inan example, LCID for a logical channel or MAC CE may be configured forthe wireless device by the base station. The MAC sub-headercorresponding to a MAC CE or a MAC SDU may comprise LCID associated withthe MAC CE or the MAC SDU.

In an example, a base station may activate and/or deactivate and/orimpact one or more processes (e.g., set values of one or more parametersof the one or more processes or start and/or stop one or more timers ofthe one or more processes) at the wireless device by employing one ormore MAC commands. The one or more MAC commands may comprise one or moreMAC control elements. In an example, the one or more processes maycomprise activation and/or deactivation of PDCP packet duplication forone or more radio bearers. The base station may transmit a MAC CEcomprising one or more fields, the values of the fields indicatingactivation and/or deactivation of PDCP duplication for the one or moreradio bearers. In an example, the one or more processes may compriseChannel State Information (CSI) transmission of on one or more cells.The base station may transmit one or more MAC CEs indicating activationand/or deactivation of the CSI transmission on the one or more cells. Inan example, the one or more processes may comprise activation ordeactivation of one or more secondary cells. In an example, the basestation may transmit a MA CE indicating activation or deactivation ofone or more secondary cells. In an example, the base station maytransmit one or more MAC CEs indicating starting and/or stopping one ormore Discontinuous Reception (DRX) timers at the wireless device. In anexample, the base station may transmit one or more MAC CEs indicatingone or more timing advance values for one or more Timing Advance Groups(TAGs).

FIG. 3 is a block diagram of base stations (base station 1, 120A, andbase station 2, 120B) and a wireless device 110. A wireless device maybe called an UE. A base station may be called a NB, eNB, gNB, and/orng-eNB. In an example, a wireless device and/or a base station may actas a relay node. The base station 1, 120A, may comprise at least onecommunication interface 320A (e.g. a wireless modem, an antenna, a wiredmodem, and/or the like), at least one processor 321A, and at least oneset of program code instructions 323A stored in non-transitory memory322A and executable by the at least one processor 321A. The base station2, 120B, may comprise at least one communication interface 320B, atleast one processor 321B, and at least one set of program codeinstructions 323B stored in non-transitory memory 322B and executable bythe at least one processor 321B.

A base station may comprise many sectors for example: 1, 2, 3, 4, or 6sectors. A base station may comprise many cells, for example, rangingfrom 1 to 50 cells or more. A cell may be categorized, for example, as aprimary cell or secondary cell. At Radio Resource Control (RRC)connection establishment/re-establishment/handover, one serving cell mayprovide the NAS (non-access stratum) mobility information (e.g. TrackingArea Identifier (TAI)). At RRC connection re-establishment/handover, oneserving cell may provide the security input. This cell may be referredto as the Primary Cell (PCell). In the downlink, a carrier correspondingto the PCell may be a DL Primary Component Carrier (PCC), while in theuplink, a carrier may be an UL PCC. Depending on wireless devicecapabilities, Secondary Cells (SCells) may be configured to formtogether with a PCell a set of serving cells. In a downlink, a carriercorresponding to an SCell may be a downlink secondary component carrier(DL SCC), while in an uplink, a carrier may be an uplink secondarycomponent carrier (UL SCC). An SCell may or may not have an uplinkcarrier.

A cell, comprising a downlink carrier and optionally an uplink carrier,may be assigned a physical cell ID and a cell index. A carrier (downlinkor uplink) may belong to one cell. The cell ID or cell index may alsoidentify the downlink carrier or uplink carrier of the cell (dependingon the context it is used). In the disclosure, a cell ID may be equallyreferred to a carrier ID, and a cell index may be referred to a carrierindex. In an implementation, a physical cell ID or a cell index may beassigned to a cell. A cell ID may be determined using a synchronizationsignal transmitted on a downlink carrier. A cell index may be determinedusing RRC messages. For example, when the disclosure refers to a firstphysical cell ID for a first downlink carrier, the disclosure may meanthe first physical cell ID is for a cell comprising the first downlinkcarrier. The same concept may apply to, for example, carrier activation.When the disclosure indicates that a first carrier is activated, thespecification may equally mean that a cell comprising the first carrieris activated.

A base station may transmit to a wireless device one or more messages(e.g. RRC messages) comprising a plurality of configuration parametersfor one or more cells. One or more cells may comprise at least oneprimary cell and at least one secondary cell. In an example, an RRCmessage may be broadcasted or unicasted to the wireless device. In anexample, configuration parameters may comprise common parameters anddedicated parameters.

Services and/or functions of an RRC sublayer may comprise at least oneof: broadcast of system information related to AS and NAS; paginginitiated by 5GC and/or NG-RAN; establishment, maintenance, and/orrelease of an RRC connection between a wireless device and NG-RAN, whichmay comprise at least one of addition, modification and release ofcarrier aggregation; or addition, modification, and/or release of dualconnectivity in NR or between E-UTRA and NR. Services and/or functionsof an RRC sublayer may further comprise at least one of securityfunctions comprising key management; establishment, configuration,maintenance, and/or release of Signaling Radio Bearers (SRBs) and/orData Radio Bearers (DRBs); mobility functions which may comprise atleast one of a handover (e.g. intra NR mobility or inter-RAT mobility)and a context transfer; or a wireless device cell selection andreselection and control of cell selection and reselection. Servicesand/or functions of an RRC sublayer may further comprise at least one ofQoS management functions; a wireless device measurementconfiguration/reporting; detection of and/or recovery from radio linkfailure; or NAS message transfer to/from a core network entity (e.g.AMF, Mobility Management Entity (MME)) from/to the wireless device.

An RRC sublayer may support an RRC_Idle state, an RRC_Inactive stateand/or an RRC_Connected state for a wireless device. In an RRC_Idlestate, a wireless device may perform at least one of: Public Land MobileNetwork (PLMN) selection; receiving broadcasted system information; cellselection/re-selection; monitoring/receiving a paging for mobileterminated data initiated by 5GC; paging for mobile terminated data areamanaged by 5GC; or DRX for CN paging configured via NAS. In anRRC_Inactive state, a wireless device may perform at least one of:receiving broadcasted system information; cell selection/re-selection;monitoring/receiving a RAN/CN paging initiated by NG-RAN/5GC; RAN-basednotification area (RNA) managed by NG-RAN; or DRX for RAN/CN pagingconfigured by NG-RAN/NAS. In an RRC_Idle state of a wireless device, abase station (e.g. NG-RAN) may keep a 5GC-NG-RAN connection (bothC/U-planes) for the wireless device; and/or store a UE AS context forthe wireless device. In an RRC_Connected state of a wireless device, abase station (e.g. NG-RAN) may perform at least one of: establishment of5GC-NG-RAN connection (both C/U-planes) for the wireless device; storinga UE AS context for the wireless device; transmit/receive of unicastdata to/from the wireless device; or network-controlled mobility basedon measurement results received from the wireless device. In anRRC_Connected state of a wireless device, an NG-RAN may know a cell thatthe wireless device belongs to.

System information (SI) may be divided into minimum SI and other SI. Theminimum SI may be periodically broadcast. The minimum SI may comprisebasic information required for initial access and information foracquiring any other SI broadcast periodically or provisioned on-demand,i.e. scheduling information. The other SI may either be broadcast, or beprovisioned in a dedicated manner, either triggered by a network or uponrequest from a wireless device. A minimum SI may be transmitted via twodifferent downlink channels using different messages (e.g.MasterInformationBlock and SystemInformationBlockType1). An other SI maybe transmitted via SystemInformationBlockType2. For a wireless device inan RRC_Connected state, dedicated RRC signalling may be employed for therequest and delivery of the other SI. For the wireless device in theRRC_Idle state and/or the RRC_Inactive state, the request may trigger arandom-access procedure.

A wireless device may report its radio access capability informationwhich may be static. A base station may request what capabilities for awireless device to report based on band information. When allowed by anetwork, a temporary capability restriction request may be sent by thewireless device to signal the limited availability of some capabilities(e.g. due to hardware sharing, interference or overheating) to the basestation. The base station may confirm or reject the request. Thetemporary capability restriction may be transparent to 5GC (e.g., onlystatic capabilities may be stored in 5GC).

When CA is configured, a wireless device may have an RRC connection witha network. At RRC connection establishment/re-establishment/handoverprocedure, one serving cell may provide NAS mobility information, and atRRC connection re-establishment/handover, one serving cell may provide asecurity input. This cell may be referred to as the PCell. Depending onthe capabilities of the wireless device, SCells may be configured toform together with the PCell a set of serving cells. The configured setof serving cells for the wireless device may comprise one PCell and oneor more SCells.

The reconfiguration, addition and removal of SCells may be performed byRRC. At intra-NR handover, RRC may also add, remove, or reconfigureSCells for usage with the target PCell. When adding a new SCell,dedicated RRC signalling may be employed to send all required systeminformation of the SCell i.e. while in connected mode, wireless devicesmay not need to acquire broadcasted system information directly from theSCells.

The purpose of an RRC connection reconfiguration procedure may be tomodify an RRC connection, (e.g. to establish, modify and/or release RBs,to perform handover, to setup, modify, and/or release measurements, toadd, modify, and/or release SCells and cell groups). As part of the RRCconnection reconfiguration procedure, NAS dedicated information may betransferred from the network to the wireless device. TheRRCConnectionReconfiguration message may be a command to modify an RRCconnection. It may convey information for measurement configuration,mobility control, radio resource configuration (e.g. RBs, MAC mainconfiguration and physical channel configuration) comprising anyassociated dedicated NAS information and security configuration. If thereceived RRC Connection Reconfiguration message includes thesCellToReleaseList, the wireless device may perform an SCell release. Ifthe received RRC Connection Reconfiguration message includes thesCellToAddModList, the wireless device may perform SCell additions ormodification.

An RRC connection establishment (or reestablishment, resume) proceduremay be to establish (or reestablish, resume) an RRC connection. an RRCconnection establishment procedure may comprise SRB1 establishment. TheRRC connection establishment procedure may be used to transfer theinitial NAS dedicated information/message from a wireless device toE-UTRAN. The RRCConnectionReestablishment message may be used tore-establish SRB1.

A measurement report procedure may be to transfer measurement resultsfrom a wireless device to NG-RAN. The wireless device may initiate ameasurement report procedure after successful security activation. Ameasurement report message may be employed to transmit measurementresults.

The wireless device 110 may comprise at least one communicationinterface 310 (e.g. a wireless modem, an antenna, and/or the like), atleast one processor 314, and at least one set of program codeinstructions 316 stored in non-transitory memory 315 and executable bythe at least one processor 314. The wireless device 110 may furthercomprise at least one of at least one speaker/microphone 311, at leastone keypad 312, at least one display/touchpad 313, at least one powersource 317, at least one global positioning system (GPS) chipset 318,and other peripherals 319.

The processor 314 of the wireless device 110, the processor 321A of thebase station 1 120A, and/or the processor 321B of the base station 2120B may comprise at least one of a general-purpose processor, a digitalsignal processor (DSP), a controller, a microcontroller, an applicationspecific integrated circuit (ASIC), a field programmable gate array(FPGA) and/or other programmable logic device, discrete gate and/ortransistor logic, discrete hardware components, and the like. Theprocessor 314 of the wireless device 110, the processor 321A in basestation 1 120A, and/or the processor 321B in base station 2 120B mayperform at least one of signal coding/processing, data processing, powercontrol, input/output processing, and/or any other functionality thatmay enable the wireless device 110, the base station 1 120A and/or thebase station 2 120B to operate in a wireless environment.

The processor 314 of the wireless device 110 may be connected to thespeaker/microphone 311, the keypad 312, and/or the display/touchpad 313.The processor 314 may receive user input data from and/or provide useroutput data to the speaker/microphone 311, the keypad 312, and/or thedisplay/touchpad 313. The processor 314 in the wireless device 110 mayreceive power from the power source 317 and/or may be configured todistribute the power to the other components in the wireless device 110.The power source 317 may comprise at least one of one or more dry cellbatteries, solar cells, fuel cells, and the like. The processor 314 maybe connected to the GPS chipset 318. The GPS chipset 318 may beconfigured to provide geographic location information of the wirelessdevice 110.

The processor 314 of the wireless device 110 may further be connected toother peripherals 319, which may comprise one or more software and/orhardware modules that provide additional features and/orfunctionalities. For example, the peripherals 319 may comprise at leastone of an accelerometer, a satellite transceiver, a digital camera, auniversal serial bus (USB) port, a hands-free headset, a frequencymodulated (FM) radio unit, a media player, an Internet browser, and thelike.

The communication interface 320A of the base station 1, 120A, and/or thecommunication interface 320B of the base station 2, 120B, may beconfigured to communicate with the communication interface 310 of thewireless device 110 via a wireless link 330A and/or a wireless link 330Brespectively. In an example, the communication interface 320A of thebase station 1, 120A, may communicate with the communication interface320B of the base station 2 and other RAN and core network nodes.

The wireless link 330A and/or the wireless link 330B may comprise atleast one of a bi-directional link and/or a directional link. Thecommunication interface 310 of the wireless device 110 may be configuredto communicate with the communication interface 320A of the base station1 120A and/or with the communication interface 320B of the base station2 120B. The base station 1 120A and the wireless device 110 and/or thebase station 2 120B and the wireless device 110 may be configured tosend and receive transport blocks via the wireless link 330A and/or viathe wireless link 330B, respectively. The wireless link 330A and/or thewireless link 330B may employ at least one frequency carrier. Accordingto some of various aspects of embodiments, transceiver(s) may beemployed. A transceiver may be a device that comprises both atransmitter and a receiver. Transceivers may be employed in devices suchas wireless devices, base stations, relay nodes, and/or the like.Example embodiments for radio technology implemented in thecommunication interface 310, 320A, 320B and the wireless link 330A, 330Bare illustrated in FIG. 4A, FIG. 4B, FIG. 4C, FIG. 4D, FIG. 6 , FIG. 7A,FIG. 7B, FIG. 8 , and associated text.

In an example, other nodes in a wireless network (e.g. AMF, UPF, SMF,etc.) may comprise one or more communication interfaces, one or moreprocessors, and memory storing instructions.

A node (e.g. wireless device, base station, AMF, SMF, UPF, servers,switches, antennas, and/or the like) may comprise one or moreprocessors, and memory storing instructions that when executed by theone or more processors causes the node to perform certain processesand/or functions. Example embodiments may enable operation ofsingle-carrier and/or multi-carrier communications. Other exampleembodiments may comprise a non-transitory tangible computer readablemedia comprising instructions executable by one or more processors tocause operation of single-carrier and/or multi-carrier communications.Yet other example embodiments may comprise an article of manufacturethat comprises a non-transitory tangible computer readablemachine-accessible medium having instructions encoded thereon forenabling programmable hardware to cause a node to enable operation ofsingle-carrier and/or multi-carrier communications. The node may includeprocessors, memory, interfaces, and/or the like.

An interface may comprise at least one of a hardware interface, afirmware interface, a software interface, and/or a combination thereof.The hardware interface may comprise connectors, wires, electronicdevices such as drivers, amplifiers, and/or the like. The softwareinterface may comprise code stored in a memory device to implementprotocol(s), protocol layers, communication drivers, device drivers,combinations thereof, and/or the like. The firmware interface maycomprise a combination of embedded hardware and code stored in and/or incommunication with a memory device to implement connections, electronicdevice operations, protocol(s), protocol layers, communication drivers,device drivers, hardware operations, combinations thereof, and/or thelike.

FIG. 4A, FIG. 4B, FIG. 4C and FIG. 4D are example diagrams for uplinkand downlink signal transmission as per an aspect of an embodiment ofthe present disclosure. FIG. 4A shows an example uplink transmitter forat least one physical channel. A baseband signal representing a physicaluplink shared channel may perform one or more functions. The one or morefunctions may comprise at least one of: scrambling; modulation ofscrambled bits to generate complex-valued symbols; mapping of thecomplex-valued modulation symbols onto one or several transmissionlayers; transform precoding to generate complex-valued symbols;precoding of the complex-valued symbols; mapping of precodedcomplex-valued symbols to resource elements; generation ofcomplex-valued time-domain Single Carrier-Frequency Division MultipleAccess (SC-FDMA) or CP-OFDM signal for an antenna port; and/or the like.In an example, when transform precoding is enabled, a SC-FDMA signal foruplink transmission may be generated. In an example, when transformprecoding is not enabled, an CP-OFDM signal for uplink transmission maybe generated by FIG. 4A. These functions are illustrated as examples andit is anticipated that other mechanisms may be implemented in variousembodiments.

An example structure for modulation and up-conversion to the carrierfrequency of the complex-valued SC-FDMA or CP-OFDM baseband signal foran antenna port and/or the complex-valued Physical Random Access CHannel(PRACH) baseband signal is shown in FIG. 4B. Filtering may be employedprior to transmission.

An example structure for downlink transmissions is shown in FIG. 4C. Thebaseband signal representing a downlink physical channel may perform oneor more functions. The one or more functions may comprise: scrambling ofcoded bits in a codeword to be transmitted on a physical channel;modulation of scrambled bits to generate complex-valued modulationsymbols; mapping of the complex-valued modulation symbols onto one orseveral transmission layers; precoding of the complex-valued modulationsymbols on a layer for transmission on the antenna ports; mapping ofcomplex-valued modulation symbols for an antenna port to resourceelements; generation of complex-valued time-domain OFDM signal for anantenna port; and/or the like. These functions are illustrated asexamples and it is anticipated that other mechanisms may be implementedin various embodiments.

In an example, a gNB may transmit a first symbol and a second symbol onan antenna port, to a wireless device. The wireless device may infer thechannel (e.g., fading gain, multipath delay, etc.) for conveying thesecond symbol on the antenna port, from the channel for conveying thefirst symbol on the antenna port. In an example, a first antenna portand a second antenna port may be quasi co-located if one or morelarge-scale properties of the channel over which a first symbol on thefirst antenna port is conveyed may be inferred from the channel overwhich a second symbol on a second antenna port is conveyed. The one ormore large-scale properties may comprise at least one of: delay spread;doppler spread; doppler shift; average gain; average delay; and/orspatial Receiving (Rx) parameters.

An example modulation and up-conversion to the carrier frequency of thecomplex-valued OFDM baseband signal for an antenna port is shown in FIG.4D. Filtering may be employed prior to transmission.

FIG. 5A is a diagram of an example uplink channel mapping and exampleuplink physical signals. FIG. 5B is a diagram of an example downlinkchannel mapping and a downlink physical signals. In an example, aphysical layer may provide one or more information transfer services toa MAC and/or one or more higher layers. For example, the physical layermay provide the one or more information transfer services to the MAC viaone or more transport channels. An information transfer service mayindicate how and with what characteristics data are transferred over theradio interface.

In an example embodiment, a radio network may comprise one or moredownlink and/or uplink transport channels. For example, a diagram inFIG. 5A shows example uplink transport channels comprising Uplink-SharedCHannel (UL-SCH) 501 and Random Access CHannel (RACH) 502. A diagram inFIG. 5B shows example downlink transport channels comprisingDownlink-Shared CHannel (DL-SCH) 511, Paging CHannel (PCH) 512, andBroadcast CHannel (BCH) 513. A transport channel may be mapped to one ormore corresponding physical channels. For example, UL-SCH 501 may bemapped to Physical Uplink Shared CHannel (PUSCH) 503. RACH 502 may bemapped to PRACH 505. DL-SCH 511 and PCH 512 may be mapped to PhysicalDownlink Shared CHannel (PDSCH) 514. BCH 513 may be mapped to PhysicalBroadcast CHannel (PBCH) 516.

There may be one or more physical channels without a correspondingtransport channel. The one or more physical channels may be employed forUplink Control Information (UCI) 509 and/or Downlink Control Information(DCI) 517. For example, Physical Uplink Control CHannel (PUCCH) 504 maycarry UCI 509 from a UE to a base station. For example, PhysicalDownlink Control CHannel (PDCCH) 515 may carry DCI 517 from a basestation to a UE. NR may support UCI 509 multiplexing in PUSCH 503 whenUCI 509 and PUSCH 503 transmissions may coincide in a slot at least inpart. The UCI 509 may comprise at least one of CSI, Acknowledgement(ACK)/Negative Acknowledgement (NACK), and/or scheduling request. TheDCI 517 on PDCCH 515 may indicate at least one of following: one or moredownlink assignments and/or one or more uplink scheduling grants

In uplink, a UE may transmit one or more Reference Signals (RSs) to abase station. For example, the one or more RSs may be at least one ofDemodulation-RS (DM-RS) 506, Phase Tracking-RS (PT-RS) 507, and/orSounding RS (SRS) 508. In downlink, a base station may transmit (e.g.,unicast, multicast, and/or broadcast) one or more RSs to a UE. Forexample, the one or more RSs may be at least one of PrimarySynchronization Signal (PSS)/Secondary Synchronization Signal (SSS) 521,CSI-RS 522, DM-RS 523, and/or PT-RS 524.

In an example, a UE may transmit one or more uplink DM-RSs 506 to a basestation for channel estimation, for example, for coherent demodulationof one or more uplink physical channels (e.g., PUSCH 503 and/or PUCCH504). For example, a UE may transmit a base station at least one uplinkDM-RS 506 with PUSCH 503 and/or PUCCH 504, wherein the at least oneuplink DM-RS 506 may be spanning a same frequency range as acorresponding physical channel. In an example, a base station mayconfigure a UE with one or more uplink DM-RS configurations. At leastone DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). One or more additional uplink DM-RS may beconfigured to transmit at one or more symbols of a PUSCH and/or PUCCH. Abase station may semi-statistically configure a UE with a maximum numberof front-loaded DM-RS symbols for PUSCH and/or PUCCH. For example, a UEmay schedule a single-symbol DM-RS and/or double symbol DM-RS based on amaximum number of front-loaded DM-RS symbols, wherein a base station mayconfigure the UE with one or more additional uplink DM-RS for PUSCHand/or PUCCH. A new radio network may support, e.g., at least forCP-OFDM, a common DM-RS structure for DL and UL, wherein a DM-RSlocation, DM-RS pattern, and/or scrambling sequence may be same ordifferent.

In an example, whether uplink PT-RS 507 is present or not may depend ona RRC configuration. For example, a presence of uplink PT-RS may beUE-specifically configured. For example, a presence and/or a pattern ofuplink PT-RS 507 in a scheduled resource may be UE-specificallyconfigured by a combination of RRC signaling and/or association with oneor more parameters employed for other purposes (e.g., Modulation andCoding Scheme (MCS)) which may be indicated by DCI. When configured, adynamic presence of uplink PT-RS 507 may be associated with one or moreDCI parameters comprising at least MCS. A radio network may supportplurality of uplink PT-RS densities defined in time/frequency domain.When present, a frequency domain density may be associated with at leastone configuration of a scheduled bandwidth. A UE may assume a sameprecoding for a DMRS port and a PT-RS port. A number of PT-RS ports maybe fewer than a number of DM-RS ports in a scheduled resource. Forexample, uplink PT-RS 507 may be confined in the scheduledtime/frequency duration for a UE.

In an example, a UE may transmit SRS 508 to a base station for channelstate estimation to support uplink channel dependent scheduling and/orlink adaptation. For example, SRS 508 transmitted by a UE may allow fora base station to estimate an uplink channel state at one or moredifferent frequencies. A base station scheduler may employ an uplinkchannel state to assign one or more resource blocks of good quality foran uplink PUSCH transmission from a UE. A base station maysemi-statistically configure a UE with one or more SRS resource sets.For an SRS resource set, a base station may configure a UE with one ormore SRS resources. An SRS resource set applicability may be configuredby a higher layer (e.g., RRC) parameter. For example, when a higherlayer parameter indicates beam management, a SRS resource in each of oneor more SRS resource sets may be transmitted at a time instant. A UE maytransmit one or more SRS resources in different SRS resource setssimultaneously. A new radio network may support aperiodic, periodicand/or semi-persistent SRS transmissions. A UE may transmit SRSresources based on one or more trigger types, wherein the one or moretrigger types may comprise higher layer signaling (e.g., RRC) and/or oneor more DCI formats (e.g., at least one DCI format may be employed for aUE to select at least one of one or more configured SRS resource sets.An SRS trigger type 0 may refer to an SRS triggered based on a higherlayer signaling. An SRS trigger type 1 may refer to an SRS triggeredbased on one or more DCI formats. In an example, when PUSCH 503 and SRS508 are transmitted in a same slot, a UE may be configured to transmitSRS 508 after a transmission of PUSCH 503 and corresponding uplink DM-RS506.

In an example, a base station may semi-statistically configure a UE withone or more SRS configuration parameters indicating at least one offollowing: a SRS resource configuration identifier, a number of SRSports, time domain behavior of SRS resource configuration (e.g., anindication of periodic, semi-persistent, or aperiodic SRS), slot(mini-slot, and/or subframe) level periodicity and/or offset for aperiodic and/or aperiodic SRS resource, a number of OFDM symbols in aSRS resource, starting OFDM symbol of a SRS resource, a SRS bandwidth, afrequency hopping bandwidth, a cyclic shift, and/or a SRS sequence ID.

In an example, in a time domain, an SS/PBCH block may comprise one ormore OFDM symbols (e.g., 4 OFDM symbols numbered in increasing orderfrom 0 to 3) within the SS/PBCH block. An SS/PBCH block may comprisePSS/SSS 521 and PBCH 516. In an example, in the frequency domain, anSS/PBCH block may comprise one or more contiguous subcarriers (e.g., 240contiguous subcarriers with the subcarriers numbered in increasing orderfrom 0 to 239) within the SS/PBCH block. For example, a PSS/SSS 521 mayoccupy 1 OFDM symbol and 127 subcarriers. For example, PBCH 516 may spanacross 3 OFDM symbols and 240 subcarriers. A UE may assume that one ormore SS/PBCH blocks transmitted with a same block index may be quasico-located, e.g., with respect to Doppler spread, Doppler shift, averagegain, average delay, and spatial Rx parameters. A UE may not assumequasi co-location for other SS/PBCH block transmissions. A periodicityof an SS/PBCH block may be configured by a radio network (e.g., by anRRC signaling) and one or more time locations where the SS/PBCH blockmay be sent may be determined by sub-carrier spacing. In an example, aUE may assume a band-specific sub-carrier spacing for an SS/PBCH blockunless a radio network has configured a UE to assume a differentsub-carrier spacing.

In an example, downlink CSI-RS 522 may be employed for a UE to acquirechannel state information. A radio network may support periodic,aperiodic, and/or semi-persistent transmission of downlink CSI-RS 522.For example, a base station may semi-statistically configure and/orreconfigure a UE with periodic transmission of downlink CSI-RS 522. Aconfigured CSI-RS resources may be activated ad/or deactivated. Forsemi-persistent transmission, an activation and/or deactivation ofCSI-RS resource may be triggered dynamically. In an example, CSI-RSconfiguration may comprise one or more parameters indicating at least anumber of antenna ports. For example, a base station may configure a UEwith 32 ports. A base station may semi-statistically configure a UE withone or more CSI-RS resource sets. One or more CSI-RS resources may beallocated from one or more CSI-RS resource sets to one or more UEs. Forexample, a base station may semi-statistically configure one or moreparameters indicating CSI RS resource mapping, for example, time-domainlocation of one or more CSI-RS resources, a bandwidth of a CSI-RSresource, and/or a periodicity. In an example, a UE may be configured toemploy a same OFDM symbols for downlink CSI-RS 522 and Control ResourceSet (CORESET) when the downlink CSI-RS 522 and CORESET are spatiallyquasi co-located and resource elements associated with the downlinkCSI-RS 522 are the outside of PRBs configured for CORESET. In anexample, a UE may be configured to employ a same OFDM symbols fordownlink CSI-RS 522 and SSB/PBCH when the downlink CSI-RS 522 andSSB/PBCH are spatially quasi co-located and resource elements associatedwith the downlink CSI-RS 522 are the outside of PRBs configured forSSB/PBCH.

In an example, a UE may transmit one or more downlink DM-RSs 523 to abase station for channel estimation, for example, for coherentdemodulation of one or more downlink physical channels (e.g., PDSCH514). For example, a radio network may support one or more variableand/or configurable DM-RS patterns for data demodulation. At least onedownlink DM-RS configuration may support a front-loaded DM-RS pattern. Afront-loaded DM-RS may be mapped over one or more OFDM symbols (e.g., 1or 2 adjacent OFDM symbols). A base station may semi-statisticallyconfigure a UE with a maximum number of front-loaded DM-RS symbols forPDSCH 514. For example, a DM-RS configuration may support one or moreDM-RS ports. For example, for single user-MIMO, a DM-RS configurationmay support at least 8 orthogonal downlink DM-RS ports. For example, formultiuser-MIMO, a DM-RS configuration may support 12 orthogonal downlinkDM-RS ports. A radio network may support, e.g., at least for CP-OFDM, acommon DM-RS structure for DL and UL, wherein a DM-RS location, DM-RSpattern, and/or scrambling sequence may be same or different.

In an example, whether downlink PT-RS 524 is present or not may dependon a RRC configuration. For example, a presence of downlink PT-RS 524may be UE-specifically configured. For example, a presence and/or apattern of downlink PT-RS 524 in a scheduled resource may beUE-specifically configured by a combination of RRC signaling and/orassociation with one or more parameters employed for other purposes(e.g., MCS) which may be indicated by DCI. When configured, a dynamicpresence of downlink PT-RS 524 may be associated with one or more DCIparameters comprising at least MCS. A radio network may supportplurality of PT-RS densities defined in time/frequency domain. Whenpresent, a frequency domain density may be associated with at least oneconfiguration of a scheduled bandwidth. A UE may assume a same precodingfor a DMRS port and a PT-RS port. A number of PT-RS ports may be fewerthan a number of DM-RS ports in a scheduled resource. For example,downlink PT-RS 524 may be confined in the scheduled time/frequencyduration for a UE.

FIG. 6 is a diagram depicting an example transmission time and receptiontime for a carrier as per an aspect of an embodiment of the presentdisclosure. A multicarrier OFDM communication system may include one ormore carriers, for example, ranging from 1 to 32 carriers, in case ofcarrier aggregation, or ranging from 1 to 64 carriers, in case of dualconnectivity. Different radio frame structures may be supported (e.g.,for FDD and for TDD duplex mechanisms). FIG. 6 shows an example frametiming. Downlink and uplink transmissions may be organized into radioframes 601. In this example, radio frame duration is 10 ms. In thisexample, a 10 ms radio frame 601 may be divided into ten equally sizedsubframes 602 with 1 ms duration. Subframe(s) may comprise one or moreslots (e.g. slots 603 and 605) depending on subcarrier spacing and/or CPlength. For example, a subframe with 15 kHz, 30 kHz, 60 kHz, 120 kHz,240 kHz and 480 kHz subcarrier spacing may comprise one, two, four,eight, sixteen and thirty-two slots, respectively. In FIG. 6 , asubframe may be divided into two equally sized slots 603 with 0.5 msduration. For example, 10 subframes may be available for downlinktransmission and 10 subframes may be available for uplink transmissionsin a 10 ms interval. Uplink and downlink transmissions may be separatedin the frequency domain. Slot(s) may include a plurality of OFDM symbols604. The number of OFDM symbols 604 in a slot 605 may depend on thecyclic prefix length. For example, a slot may be 14 OFDM symbols for thesame subcarrier spacing of up to 480 kHz with normal CP. A slot may be12 OFDM symbols for the same subcarrier spacing of 60 kHz with extendedCP. A slot may contain downlink, uplink, or a downlink part and anuplink part and/or alike.

FIG. 7A is a diagram depicting example sets of OFDM subcarriers as peran aspect of an embodiment of the present disclosure. In the example, agNB may communicate with a wireless device with a carrier with anexample channel bandwidth 700. Arrow(s) in the diagram may depict asubcarrier in a multicarrier OFDM system. The OFDM system may usetechnology such as OFDM technology, SC-FDMA technology, and/or the like.In an example, an arrow 701 shows a subcarrier transmitting informationsymbols. In an example, a subcarrier spacing 702, between two contiguoussubcarriers in a carrier, may be any one of 15 KHz, 30 KHz, 60 KHz, 120KHz, 240 KHz etc. In an example, different subcarrier spacing maycorrespond to different transmission numerologies. In an example, atransmission numerology may comprise at least: a numerology index; avalue of subcarrier spacing; a type of cyclic prefix (CP). In anexample, a gNB may transmit to/receive from a UE on a number ofsubcarriers 703 in a carrier. In an example, a bandwidth occupied by anumber of subcarriers 703 (transmission bandwidth) may be smaller thanthe channel bandwidth 700 of a carrier, due to guard band 704 and 705.In an example, a guard band 704 and 705 may be used to reduceinterference to and from one or more neighbor carriers. A number ofsubcarriers (transmission bandwidth) in a carrier may depend on thechannel bandwidth of the carrier and the subcarrier spacing. Forexample, a transmission bandwidth, for a carrier with 20 MHz channelbandwidth and 15 KHz subcarrier spacing, may be in number of 1024subcarriers.

In an example, a gNB and a wireless device may communicate with multipleCCs when configured with CA. In an example, different component carriersmay have different bandwidth and/or subcarrier spacing, if CA issupported. In an example, a gNB may transmit a first type of service toa UE on a first component carrier. The gNB may transmit a second type ofservice to the UE on a second component carrier. Different type ofservices may have different service requirement (e.g., data rate,latency, reliability), which may be suitable for transmission viadifferent component carrier having different subcarrier spacing and/orbandwidth. FIG. 7B shows an example embodiment. A first componentcarrier may comprise a first number of subcarriers 706 with a firstsubcarrier spacing 709. A second component carrier may comprise a secondnumber of subcarriers 707 with a second subcarrier spacing 710. A thirdcomponent carrier may comprise a third number of subcarriers 708 with athird subcarrier spacing 711. Carriers in a multicarrier OFDMcommunication system may be contiguous carriers, non-contiguouscarriers, or a combination of both contiguous and non-contiguouscarriers.

FIG. 8 is a diagram depicting OFDM radio resources as per an aspect ofan embodiment of the present disclosure. In an example, a carrier mayhave a transmission bandwidth 801. In an example, a resource grid may bein a structure of frequency domain 802 and time domain 803. In anexample, a resource grid may comprise a first number of OFDM symbols ina subframe and a second number of resource blocks, starting from acommon resource block indicated by higher-layer signaling (e.g. RRCsignaling), for a transmission numerology and a carrier. In an example,in a resource grid, a resource unit identified by a subcarrier index anda symbol index may be a resource element 805. In an example, a subframemay comprise a first number of OFDM symbols 807 depending on anumerology associated with a carrier. For example, when a subcarrierspacing of a numerology of a carrier is 15 KHz, a subframe may have 14OFDM symbols for a carrier. When a subcarrier spacing of a numerology is30 KHz, a subframe may have 28 OFDM symbols. When a subcarrier spacingof a numerology is 60 Khz, a subframe may have 56 OFDM symbols, etc. Inan example, a second number of resource blocks comprised in a resourcegrid of a carrier may depend on a bandwidth and a numerology of thecarrier.

As shown in FIG. 8 , a resource block 806 may comprise 12 subcarriers.In an example, multiple resource blocks may be grouped into a ResourceBlock Group (RBG) 804. In an example, a size of a RBG may depend on atleast one of: a RRC message indicating a RBG size configuration; a sizeof a carrier bandwidth; or a size of a bandwidth part of a carrier. Inan example, a carrier may comprise multiple bandwidth parts. A firstbandwidth part of a carrier may have different frequency location and/orbandwidth from a second bandwidth part of the carrier.

In an example, a gNB may transmit a downlink control informationcomprising a downlink or uplink resource block assignment to a wirelessdevice. A base station may transmit to or receive from, a wirelessdevice, data packets (e.g. transport blocks) scheduled and transmittedvia one or more resource blocks and one or more slots according toparameters in a downlink control information and/or RRC message(s). Inan example, a starting symbol relative to a first slot of the one ormore slots may be indicated to the wireless device. In an example, a gNBmay transmit to or receive from, a wireless device, data packetsscheduled on one or more RBGs and one or more slots.

In an example, a gNB may transmit a downlink control informationcomprising a downlink assignment to a wireless device via one or morePDCCHs. The downlink assignment may comprise parameters indicating atleast modulation and coding format; resource allocation; and/or HARQinformation related to DL-SCH. In an example, a resource allocation maycomprise parameters of resource block allocation; and/or slotallocation. In an example, a gNB may dynamically allocate resources to awireless device via a Cell-Radio Network Temporary Identifier (C-RNTI)on one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible allocation when its downlink receptionis enabled. The wireless device may receive one or more downlink datapackage on one or more PDSCH scheduled by the one or more PDCCHs, whensuccessfully detecting the one or more PDCCHs.

In an example, a gNB may allocate Configured Scheduling (CS) resourcesfor down link transmission to a wireless device. The gNB may transmitone or more RRC messages indicating a periodicity of the CS grant. ThegNB may transmit a DCI via a PDCCH addressed to a ConfiguredScheduling-RNTI (CS-RNTI) activating the CS resources. The DCI maycomprise parameters indicating that the downlink grant is a CS grant.The CS grant may be implicitly reused according to the periodicitydefined by the one or more RRC messages, until deactivated.

In an example, a gNB may transmit a downlink control informationcomprising an uplink grant to a wireless device via one or more PDCCHs.The uplink grant may comprise parameters indicating at least modulationand coding format; resource allocation; and/or HARQ information relatedto UL-SCH. In an example, a resource allocation may comprise parametersof resource block allocation; and/or slot allocation. In an example, agNB may dynamically allocate resources to a wireless device via a C-RNTIon one or more PDCCHs. The wireless device may monitor the one or morePDCCHs in order to find possible resource allocation. The wirelessdevice may transmit one or more uplink data package via one or morePUSCH scheduled by the one or more PDCCHs, when successfully detectingthe one or more PDCCHs.

In an example, a gNB may allocate CS resources for uplink datatransmission to a wireless device. The gNB may transmit one or more RRCmessages indicating a periodicity of the CS grant. The gNB may transmita DCI via a PDCCH addressed to a CS-RNTI activating the CS resources.The DCI may comprise parameters indicating that the uplink grant is a CSgrant. The CS grant may be implicitly reused according to theperiodicity defined by the one or more RRC message, until deactivated.

In an example, a base station may transmit DCI/control signaling viaPDCCH. The DCI may take a format in a plurality of formats. A DCI maycomprise downlink and/or uplink scheduling information (e.g., resourceallocation information, HARQ related parameters, MCS), request for CSI(e.g., aperiodic CQI reports), request for SRS, uplink power controlcommands for one or more cells, one or more timing information (e.g., TBtransmission/reception timing, HARQ feedback timing, etc.), etc. In anexample, a DCI may indicate an uplink grant comprising transmissionparameters for one or more transport blocks. In an example, a DCI mayindicate downlink assignment indicating parameters for receiving one ormore transport blocks. In an example, a DCI may be used by base stationto initiate a contention-free random access at the wireless device. Inan example, the base station may transmit a DCI comprising slot formatindicator (SFI) notifying a slot format. In an example, the base stationmay transmit a DCI comprising pre-emption indication notifying thePRB(s) and/or OFDM symbol(s) where a UE may assume no transmission isintended for the UE. In an example, the base station may transmit a DCIfor group power control of PUCCH or PUSCH or SRS. In an example, a DCImay correspond to an RNTI. In an example, the wireless device may obtainan RNTI in response to completing the initial access (e.g., C-RNTI). Inan example, the base station may configure an RNTI for the wireless(e.g., CS-RNTI, TPC-CS-RNTI, TPC-PUCCH-RNTI, TPC-PUSCH-RNTI,TPC-SRS-RNTI). In an example, the wireless device may compute an RNTI(e.g., the wireless device may compute RA-RNTI based on resources usedfor transmission of a preamble). In an example, an RNTI may have apre-configured value (e.g., P-RNTI or SI-RNTI). In an example, awireless device may monitor a group common search space which may beused by base station for transmitting DCIs that are intended for a groupof UEs. In an example, a group common DCI may correspond to an RNTIwhich is commonly configured for a group of UEs. In an example, awireless device may monitor a UE-specific search space. In an example, aUE specific DCI may correspond to an RNTI configured for the wirelessdevice.

A NR system may support a single beam operation and/or a multi-beamoperation. In a multi-beam operation, a base station may perform adownlink beam sweeping to provide coverage for common control channelsand/or downlink SS blocks, which may comprise at least a PSS, a SSS,and/or PBCH. A wireless device may measure quality of a beam pair linkusing one or more RSs. One or more SS blocks, or one or more CSI-RSresources, associated with a CSI-RS resource index (CRI), or one or moreDM-RSs of PBCH, may be used as RS for measuring quality of a beam pairlink. Quality of a beam pair link may be defined as a reference signalreceived power (RSRP) value, or a reference signal received quality(RSRQ) value, and/or a CSI value measured on RS resources. The basestation may indicate whether an RS resource, used for measuring a beampair link quality, is quasi-co-located (QCLed) with DM-RSs of a controlchannel. A RS resource and DM-RSs of a control channel may be calledQCLed when a channel characteristics from a transmission on an RS to awireless device, and that from a transmission on a control channel to awireless device, are similar or same under a configured criterion. In amulti-beam operation, a wireless device may perform an uplink beamsweeping to access a cell.

In an example, a wireless device may be configured to monitor PDCCH onone or more beam pair links simultaneously depending on a capability ofa wireless device. This may increase robustness against beam pair linkblocking. A base station may transmit one or more messages to configurea wireless device to monitor PDCCH on one or more beam pair links indifferent PDCCH OFDM symbols. For example, a base station may transmithigher layer signaling (e.g. RRC signaling) or MAC CE comprisingparameters related to the Rx beam setting of a wireless device formonitoring PDCCH on one or more beam pair links. A base station maytransmit indication of spatial QCL assumption between an DL RS antennaport(s) (for example, cell-specific CSI-RS, or wireless device-specificCSI-RS, or SS block, or PBCH with or without DM-RSs of PBCH), and DL RSantenna port(s) for demodulation of DL control channel. Signaling forbeam indication for a PDCCH may be MAC CE signaling, or RRC signaling,or DCI signaling, or specification-transparent and/or implicit method,and combination of these signaling methods.

For reception of unicast DL data channel, a base station may indicatespatial QCL parameters between DL RS antenna port(s) and DM-RS antennaport(s) of DL data channel. The base station may transmit DCI (e.g.downlink grants) comprising information indicating the RS antennaport(s). The information may indicate RS antenna port(s) which may beQCL-ed with the DM-RS antenna port(s). Different set of DM-RS antennaport(s) for a DL data channel may be indicated as QCL with different setof the RS antenna port(s).

FIG. 9A is an example of beam sweeping in a DL channel. In anRRC_INACTIVE state or RRC_IDLE state, a wireless device may assume thatSS blocks form an SS burst 940, and an SS burst set 950. The SS burstset 950 may have a given periodicity. For example, in a multi-beamoperation, a base station 120 may transmit SS blocks in multiple beams,together forming a SS burst 940. One or more SS blocks may betransmitted on one beam. If multiple SS bursts 940 are transmitted withmultiple beams, SS bursts together may form SS burst set 950.

A wireless device may further use CSI-RS in the multi-beam operation forestimating a beam quality of a links between a wireless device and abase station. A beam may be associated with a CSI-RS. For example, awireless device may, based on a RSRP measurement on CSI-RS, report abeam index, as indicated in a CRI for downlink beam selection, andassociated with a RSRP value of a beam. A CSI-RS may be transmitted on aCSI-RS resource including at least one of one or more antenna ports, oneor more time or frequency radio resources. A CSI-RS resource may beconfigured in a cell-specific way by common RRC signaling, or in awireless device-specific way by dedicated RRC signaling, and/or L1/L2signaling. Multiple wireless devices covered by a cell may measure acell-specific CSI-RS resource. A dedicated subset of wireless devicescovered by a cell may measure a wireless device-specific CSI-RSresource.

A CSI-RS resource may be transmitted periodically, or using aperiodictransmission, or using a multi-shot or semi-persistent transmission. Forexample, in a periodic transmission in FIG. 9A, a base station 120 maytransmit configured CSI-RS resources 940 periodically using a configuredperiodicity in a time domain. In an aperiodic transmission, a configuredCSI-RS resource may be transmitted in a dedicated time slot. In amulti-shot or semi-persistent transmission, a configured CSI-RS resourcemay be transmitted within a configured period. Beams used for CSI-RStransmission may have different beam width than beams used for SS-blockstransmission.

FIG. 9B is an example of a beam management procedure in an example newradio network. A base station 120 and/or a wireless device 110 mayperform a downlink L1/L2 beam management procedure. One or more of thefollowing downlink L1/L2 beam management procedures may be performedwithin one or more wireless devices 110 and one or more base stations120. In an example, a P-1 procedure 910 may be used to enable thewireless device 110 to measure one or more Transmission (Tx) beamsassociated with the base station 120 to support a selection of a firstset of Tx beams associated with the base station 120 and a first set ofRx beam(s) associated with a wireless device 110. For beamforming at abase station 120, a base station 120 may sweep a set of different TXbeams. For beamforming at a wireless device 110, a wireless device 110may sweep a set of different Rx beams. In an example, a P-2 procedure920 may be used to enable a wireless device 110 to measure one or moreTx beams associated with a base station 120 to possibly change a firstset of Tx beams associated with a base station 120. A P-2 procedure 920may be performed on a possibly smaller set of beams for beam refinementthan in the P-1 procedure 910. A P-2 procedure 920 may be a special caseof a P-1 procedure 910. In an example, a P-3 procedure 930 may be usedto enable a wireless device 110 to measure at least one Tx beamassociated with a base station 120 to change a first set of Rx beamsassociated with a wireless device 110.

A wireless device 110 may transmit one or more beam management reportsto a base station 120. In one or more beam management reports, awireless device 110 may indicate some beam pair quality parameters,comprising at least, one or more beam identifications; RSRP; PrecodingMatrix Indicator (PMI)/Channel Quality Indicator (CQI)/Rank Indicator(RI) of a subset of configured beams. Based on one or more beammanagement reports, a base station 120 may transmit to a wireless device110 a signal indicating that one or more beam pair links are one or moreserving beams. A base station 120 may transmit PDCCH and PDSCH for awireless device 110 using one or more serving beams.

In an example embodiment, new radio network may support a BandwidthAdaptation (BA). In an example, receive and/or transmit bandwidthsconfigured by an UE employing a BA may not be large. For example, areceive and/or transmit bandwidths may not be as large as a bandwidth ofa cell. Receive and/or transmit bandwidths may be adjustable. Forexample, a UE may change receive and/or transmit bandwidths, e.g., toshrink during period of low activity to save power. For example, a UEmay change a location of receive and/or transmit bandwidths in afrequency domain, e.g. to increase scheduling flexibility. For example,a UE may change a subcarrier spacing, e.g. to allow different services.

In an example embodiment, a subset of a total cell bandwidth of a cellmay be referred to as a Bandwidth Part (BWP). A base station mayconfigure a UE with one or more BWPs to achieve a BA. For example, abase station may indicate, to a UE, which of the one or more(configured) BWPs is an active BWP.

FIG. 10 is an example diagram of 3 BWPs configured: BWP1 (1010 and 1050)with a width of 40 MHz and subcarrier spacing of 15 kHz; BWP2 (1020 and1040) with a width of 10 MHz and subcarrier spacing of 15 kHz; BWP3 1030with a width of 20 MHz and subcarrier spacing of 60 kHz.

In an example, a UE, configured for operation in one or more BWPs of acell, may be configured by one or more higher layers (e.g. RRC layer)for a cell a set of one or more BWPs (e.g., at most four BWPs) forreceptions by the UE (DL BWP set) in a DL bandwidth by at least oneparameter DL-BWP and a set of one or more BWPs (e.g., at most four BWPs)for transmissions by a UE (UL BWP set) in an UL bandwidth by at leastone parameter UL-BWP for a cell.

To enable BA on the PCell, a base station may configure a UE with one ormore UL and DL BWP pairs. To enable BA on SCells (e.g., in case of CA),a base station may configure a UE at least with one or more DL BWPs(e.g., there may be none in an UL).

In an example, an initial active DL BWP may be defined by at least oneof a location and number of contiguous PRBs, a subcarrier spacing, or acyclic prefix, for a control resource set for at least one common searchspace. For operation on the PCell, one or more higher layer parametersmay indicate at least one initial UL BWP for a random access procedure.If a UE is configured with a secondary carrier on a primary cell, the UEmay be configured with an initial BWP for random access procedure on asecondary carrier.

In an example, for unpaired spectrum operation, a UE may expect that acenter frequency for a DL BWP may be same as a center frequency for a ULBWP.

For example, for a DL BWP or an UL BWP in a set of one or more DL BWPsor one or more UL BWPs, respectively, a base statin maysemi-statistically configure a UE for a cell with one or more parametersindicating at least one of following: a subcarrier spacing; a cyclicprefix; a number of contiguous PRBs; an index in the set of one or moreDL BWPs and/or one or more UL BWPs; a link between a DL BWP and an ULBWP from a set of configured DL BWPs and UL BWPs; a DCI detection to aPDSCH reception timing; a PDSCH reception to a HARQ-ACK transmissiontiming value; a DCI detection to a PUSCH transmission timing value; anoffset of a first PRB of a DL bandwidth or an UL bandwidth,respectively, relative to a first PRB of a bandwidth.

In an example, for a DL BWP in a set of one or more DL BWPs on a PCell,a base station may configure a UE with one or more control resource setsfor at least one type of common search space and/or one UE-specificsearch space. For example, a base station may not configure a UE withouta common search space on a PCell, or on a PSCell, in an active DL BWP.

For an UL BWP in a set of one or more UL BWPs, a base station mayconfigure a UE with one or more resource sets for one or more PUCCHtransmissions.

In an example, if a DCI comprises a BWP indicator field, a BWP indicatorfield value may indicate an active DL BWP, from a configured DL BWP set,for one or more DL receptions. If a DCI comprises a BWP indicator field,a BWP indicator field value may indicate an active UL BWP, from aconfigured UL BWP set, for one or more UL transmissions.

In an example, for a PCell, a base station may semi-statisticallyconfigure a UE with a default DL BWP among configured DL BWPs. If a UEis not provided a default DL BWP, a default BWP may be an initial activeDL BWP.

In an example, a base station may configure a UE with a timer value fora PCell. For example, a UE may start a timer, referred to as BWPinactivity timer, when a UE detects a DCI indicating an active DL BWP,other than a default DL BWP, for a paired spectrum operation or when aUE detects a DCI indicating an active DL BWP or UL BWP, other than adefault DL BWP or UL BWP, for an unpaired spectrum operation. The UE mayincrement the timer by an interval of a first value (e.g., the firstvalue may be 1 millisecond or 0.5 milliseconds) if the UE does notdetect a DCI during the interval for a paired spectrum operation or foran unpaired spectrum operation. In an example, the timer may expire whenthe timer is equal to the timer value. A UE may switch to the default DLBWP from an active DL BWP when the timer expires.

In an example, a base station may semi-statistically configure a UE withone or more BWPs. A UE may switch an active BWP from a first BWP to asecond BWP in response to receiving a DCI indicating the second BWP asan active BWP and/or in response to an expiry of BWP inactivity timer(for example, the second BWP may be a default BWP). For example, FIG. 10is an example diagram of 3 BWPs configured, BWP1 (1010 and 1050), BWP2(1020 and 1040), and BWP3 (1030). BWP2 (1020 and 1040) may be a defaultBWP. BWP1 (1010) may be an initial active BWP. In an example, a UE mayswitch an active BWP from BWP1 1010 to BWP2 1020 in response to anexpiry of BWP inactivity timer. For example, a UE may switch an activeBWP from BWP2 1020 to BWP3 1030 in response to receiving a DCIindicating BWP3 1030 as an active BWP. Switching an active BWP from BWP31030 to BWP2 1040 and/or from BWP2 1040 to BWP1 1050 may be in responseto receiving a DCI indicating an active BWP and/or in response to anexpiry of BWP inactivity timer.

In an example, if a UE is configured for a secondary cell with a defaultDL BWP among configured DL BWPs and a timer value, UE procedures on asecondary cell may be same as on a primary cell using the timer valuefor the secondary cell and the default DL BWP for the secondary cell.

In an example, if a base station configures a UE with a first active DLBWP and a first active UL BWP on a secondary cell or carrier, a UE mayemploy an indicated DL BWP and an indicated UL BWP on a secondary cellas a respective first active DL BWP and first active UL BWP on asecondary cell or carrier.

FIG. 11A and FIG. 11B show packet flows employing a multi connectivity(e.g. dual connectivity, multi connectivity, tight interworking, and/orthe like). FIG. 11A is an example diagram of a protocol structure of awireless device 110 (e.g. UE) with CA and/or multi connectivity as peran aspect of an embodiment. FIG. 11B is an example diagram of a protocolstructure of multiple base stations with CA and/or multi connectivity asper an aspect of an embodiment. The multiple base stations may comprisea master node, MN 1130 (e.g. a master node, a master base station, amaster gNB, a master eNB, and/or the like) and a secondary node, SN 1150(e.g. a secondary node, a secondary base station, a secondary gNB, asecondary eNB, and/or the like). A master node 1130 and a secondary node1150 may co-work to communicate with a wireless device 110.

When multi connectivity is configured for a wireless device 110, thewireless device 110, which may support multiple reception/transmissionfunctions in an RRC connected state, may be configured to utilize radioresources provided by multiple schedulers of a multiple base stations.Multiple base stations may be inter-connected via a non-ideal or idealbackhaul (e.g. Xn interface, X2 interface, and/or the like). A basestation involved in multi connectivity for a certain wireless device mayperform at least one of two different roles: a base station may eitheract as a master base station or as a secondary base station. In multiconnectivity, a wireless device may be connected to one master basestation and one or more secondary base stations. In an example, a masterbase station (e.g. the MN 1130) may provide a master cell group (MCG)comprising a primary cell and/or one or more secondary cells for awireless device (e.g. the wireless device 110). A secondary base station(e.g. the SN 1150) may provide a secondary cell group (SCG) comprising aprimary secondary cell (PSCell) and/or one or more secondary cells for awireless device (e.g. the wireless device 110).

In multi connectivity, a radio protocol architecture that a beareremploys may depend on how a bearer is setup. In an example, threedifferent type of bearer setup options may be supported: an MCG bearer,an SCG bearer, and/or a split bearer. A wireless device mayreceive/transmit packets of an MCG bearer via one or more cells of theMCG, and/or may receive/transmits packets of an SCG bearer via one ormore cells of an SCG. Multi-connectivity may also be described as havingat least one bearer configured to use radio resources provided by thesecondary base station. Multi-connectivity may or may not beconfigured/implemented in some of the example embodiments.

In an example, a wireless device (e.g. Wireless Device 110) may transmitand/or receive: packets of an MCG bearer via an SDAP layer (e.g. SDAP1110), a PDCP layer (e.g. NR PDCP 1111), an RLC layer (e.g. MN RLC1114), and a MAC layer (e.g. MN MAC 1118); packets of a split bearer viaan SDAP layer (e.g. SDAP 1110), a PDCP layer (e.g. NR PDCP 1112), one ofa master or secondary RLC layer (e.g. MN RLC 1115, SN RLC 1116), and oneof a master or secondary MAC layer (e.g. MN MAC 1118, SN MAC 1119);and/or packets of an SCG bearer via an SDAP layer (e.g. SDAP 1110), aPDCP layer (e.g. NR PDCP 1113), an RLC layer (e.g. SN RLC 1117), and aMAC layer (e.g. MN MAC 1119).

In an example, a master base station (e.g. MN 1130) and/or a secondarybase station (e.g. SN 1150) may transmit/receive: packets of an MCGbearer via a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP1140), a master or secondary node PDCP layer (e.g. NR PDCP 1121, NR PDCP1142), a master node RLC layer (e.g. MN RLC 1124, MN RLC 1125), and amaster node MAC layer (e.g. MN MAC 1128); packets of an SCG bearer via amaster or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1122, NR PDCP 1143), asecondary node RLC layer (e.g. SN RLC 1146, SN RLC 1147), and asecondary node MAC layer (e.g. SN MAC 1148); packets of a split bearervia a master or secondary node SDAP layer (e.g. SDAP 1120, SDAP 1140), amaster or secondary node PDCP layer (e.g. NR PDCP 1123, NR PDCP 1141), amaster or secondary node RLC layer (e.g. MN RLC 1126, SN RLC 1144, SNRLC 1145, MN RLC 1127), and a master or secondary node MAC layer (e.g.MN MAC 1128, SN MAC 1148).

In multi connectivity, a wireless device may configure multiple MACentities: one MAC entity (e.g. MN MAC 1118) for a master base station,and other MAC entities (e.g. SN MAC 1119) for a secondary base station.In multi-connectivity, a configured set of serving cells for a wirelessdevice may comprise two subsets: an MCG comprising serving cells of amaster base station, and SCGs comprising serving cells of a secondarybase station. For an SCG, one or more of following configurations may beapplied: at least one cell of an SCG has a configured UL CC and at leastone cell of a SCG, named as primary secondary cell (PSCell, PCell ofSCG, or sometimes called PCell), is configured with PUCCH resources;when an SCG is configured, there may be at least one SCG bearer or oneSplit bearer; upon detection of a physical layer problem or a randomaccess problem on a PSCell, or a number of NR RLC retransmissions hasbeen reached associated with the SCG, or upon detection of an accessproblem on a PSCell during a SCG addition or a SCG change: an RRCconnection re-establishment procedure may not be triggered, ULtransmissions towards cells of an SCG may be stopped, a master basestation may be informed by a wireless device of a SCG failure type, forsplit bearer, a DL data transfer over a master base station may bemaintained; an NR RLC acknowledged mode (AM) bearer may be configuredfor a split bearer; PCell and/or PSCell may not be de-activated; PSCellmay be changed with a SCG change procedure (e.g. with security keychange and a RACH procedure); and/or a bearer type change between asplit bearer and a SCG bearer or simultaneous configuration of a SCG anda split bearer may or may not supported.

With respect to interaction between a master base station and asecondary base stations for multi-connectivity, one or more of thefollowing may be applied: a master base station and/or a secondary basestation may maintain RRM measurement configurations of a wirelessdevice; a master base station may (e.g. based on received measurementreports, traffic conditions, and/or bearer types) may decide to requesta secondary base station to provide additional resources (e.g. servingcells) for a wireless device; upon receiving a request from a masterbase station, a secondary base station may create/modify a containerthat may result in configuration of additional serving cells for awireless device (or decide that the secondary base station has noresource available to do so); for a UE capability coordination, a masterbase station may provide (a part of) an AS configuration and UEcapabilities to a secondary base station; a master base station and asecondary base station may exchange information about a UE configurationby employing of RRC containers (inter-node messages) carried via Xnmessages; a secondary base station may initiate a reconfiguration of thesecondary base station existing serving cells (e.g. PUCCH towards thesecondary base station); a secondary base station may decide which cellis a PSCell within a SCG; a master base station may or may not changecontent of RRC configurations provided by a secondary base station; incase of a SCG addition and/or a SCG SCell addition, a master basestation may provide recent (or the latest) measurement results for SCGcell(s); a master base station and secondary base stations may receiveinformation of SFN and/or subframe offset of each other from OAM and/orvia an Xn interface, (e.g. for a purpose of DRX alignment and/oridentification of a measurement gap). In an example, when adding a newSCG SCell, dedicated RRC signaling may be used for sending requiredsystem information of a cell as for CA, except for a SFN acquired from aMIB of a PSCell of a SCG.

FIG. 12 is an example diagram of a random access procedure. One or moreevents may trigger a random access procedure. For example, one or moreevents may be at least one of following: initial access from RRC_IDLE,RRC connection re-establishment procedure, handover, DL or UL dataarrival during RRC_CONNECTED when UL synchronization status isnon-synchronised, transition from RRC_Inactive, and/or request for othersystem information. For example, a PDCCH order, a MAC entity, and/or abeam failure indication may initiate a random access procedure.

In an example embodiment, a random access procedure may be at least oneof a contention based random access procedure and a contention freerandom access procedure. For example, a contention based random accessprocedure may comprise, one or more Msg 1 1220 transmissions, one ormore Msg2 1230 transmissions, one or more Msg3 1240 transmissions, andcontention resolution 1250. For example, a contention free random accessprocedure may comprise one or more Msg 1 1220 transmissions and one ormore Msg2 1230 transmissions.

In an example, a base station may transmit (e.g., unicast, multicast, orbroadcast), to a UE, a RACH configuration 1210 via one or more beams.The RACH configuration 1210 may comprise one or more parametersindicating at least one of following: available set of PRACH resourcesfor a transmission of a random access preamble, initial preamble power(e.g., random access preamble initial received target power), an RSRPthreshold for a selection of a SS block and corresponding PRACHresource, a power-ramping factor (e.g., random access preamble powerramping step), random access preamble index, a maximum number ofpreamble transmission, preamble group A and group B, a threshold (e.g.,message size) to determine the groups of random access preambles, a setof one or more random access preambles for system information requestand corresponding PRACH resource(s), if any, a set of one or more randomaccess preambles for beam failure recovery request and correspondingPRACH resource(s), if any, a time window to monitor RA response(s), atime window to monitor response(s) on beam failure recovery request,and/or a contention resolution timer.

In an example, the Msg1 1220 may be one or more transmissions of arandom access preamble. For a contention based random access procedure,a UE may select a SS block with a RSRP above the RSRP threshold. Ifrandom access preambles group B exists, a UE may select one or morerandom access preambles from a group A or a group B depending on apotential Msg3 1240 size. If a random access preambles group B does notexist, a UE may select the one or more random access preambles from agroup A. A UE may select a random access preamble index randomly (e.g.with equal probability or a normal distribution) from one or more randomaccess preambles associated with a selected group. If a base stationsemi-statistically configures a UE with an association between randomaccess preambles and SS blocks, the UE may select a random accesspreamble index randomly with equal probability from one or more randomaccess preambles associated with a selected SS block and a selectedgroup.

For example, a UE may initiate a contention free random access procedurebased on a beam failure indication from a lower layer. For example, abase station may semi-statistically configure a UE with one or morecontention free PRACH resources for beam failure recovery requestassociated with at least one of SS blocks and/or CSI-RSs. If at leastone of SS blocks with a RSRP above a first RSRP threshold amongstassociated SS blocks or at least one of CSI-RSs with a RSRP above asecond RSRP threshold amongst associated CSI-RSs is available, a UE mayselect a random access preamble index corresponding to a selected SSblock or CSI-RS from a set of one or more random access preambles forbeam failure recovery request.

For example, a UE may receive, from a base station, a random accesspreamble index via PDCCH or RRC for a contention free random accessprocedure. If a base station does not configure a UE with at least onecontention free PRACH resource associated with SS blocks or CSI-RS, theUE may select a random access preamble index. If a base stationconfigures a UE with one or more contention free PRACH resourcesassociated with SS blocks and at least one SS block with a RSRP above afirst RSRP threshold amongst associated SS blocks is available, the UEmay select the at least one SS block and select a random access preamblecorresponding to the at least one SS block. If a base station configuresa UE with one or more contention free PRACH resources associated withCSI-RSs and at least one CSI-RS with a RSRP above a second RSPRthreshold amongst the associated CSI-RSs is available, the UE may selectthe at least one CSI-RS and select a random access preamblecorresponding to the at least one CSI-RS.

A UE may perform one or more Msg1 1220 transmissions by transmitting theselected random access preamble. For example, if a UE selects an SSblock and is configured with an association between one or more PRACHoccasions and one or more SS blocks, the UE may determine an PRACHoccasion from one or more PRACH occasions corresponding to a selected SSblock. For example, if a UE selects a CSI-RS and is configured with anassociation between one or more PRACH occasions and one or more CSI-RSs,the UE may determine a PRACH occasion from one or more PRACH occasionscorresponding to a selected CSI-RS. A UE may transmit, to a basestation, a selected random access preamble via a selected PRACHoccasions. A UE may determine a transmit power for a transmission of aselected random access preamble at least based on an initial preamblepower and a power-ramping factor. A UE may determine a RA-RNTIassociated with a selected PRACH occasions in which a selected randomaccess preamble is transmitted. For example, a UE may not determine aRA-RNTI for a beam failure recovery request. A UE may determine anRA-RNTI at least based on an index of a first OFDM symbol and an indexof a first slot of a selected PRACH occasions, and/or an uplink carrierindex for a transmission of Msg1 1220.

In an example, a UE may receive, from a base station, a random accessresponse, Msg 2 1230. A UE may start a time window (e.g., ra-ResponseWindow) to monitor a random access response. For beam failure recoveryrequest, a base station may configure a UE with a different time window(e.g., bfr-Response Window) to monitor response on beam failure recoveryrequest. For example, a UE may start a time window (e.g., ra-ResponseWindow or bfr-Response Window) at a start of a first PDCCH occasionafter a fixed duration of one or more symbols from an end of a preambletransmission. If a UE transmits multiple preambles, the UE may start atime window at a start of a first PDCCH occasion after a fixed durationof one or more symbols from an end of a first preamble transmission. AUE may monitor a PDCCH of a cell for at least one random access responseidentified by a RA-RNTI or for at least one response to beam failurerecovery request identified by a C-RNTI while a timer for a time windowis running.

In an example, a UE may consider a reception of random access responsesuccessful if at least one random access response comprises a randomaccess preamble identifier corresponding to a random access preambletransmitted by the UE. A UE may consider the contention free randomaccess procedure successfully completed if a reception of random accessresponse is successful. If a contention free random access procedure istriggered for a beam failure recovery request, a UE may consider acontention free random access procedure successfully complete if a PDCCHtransmission is addressed to a C-RNTI. In an example, if at least onerandom access response comprises only a random access preambleidentifier, a UE may consider the random access procedure successfullycompleted and may indicate a reception of an acknowledgement for asystem information request to upper layers. If a UE has signaledmultiple preamble transmissions, the UE may stop transmitting remainingpreambles (if any) in response to a successful reception of acorresponding random access response.

In an example, a UE may perform one or more Msg 3 1240 transmissions inresponse to a successful reception of random access response (e.g., fora contention based random access procedure). A UE may adjust an uplinktransmission timing based on a timing advanced command indicated by arandom access response and may transmit one or more transport blocksbased on an uplink grant indicated by a random access response.Subcarrier spacing for PUSCH transmission for Msg3 1240 may be providedby at least one higher layer (e.g. RRC) parameter. A UE may transmit arandom access preamble via PRACH and Msg3 1240 via PUSCH on a same cell.A base station may indicate an UL BWP for a PUSCH transmission of Msg31240 via system information block. A UE may employ HARQ for aretransmission of Msg 3 1240.

In an example, multiple UEs may perform Msg 1 1220 by transmitting asame preamble to a base station and receive, from the base station, asame random access response comprising an identity (e.g., TC-RNTI).Contention resolution 1250 may ensure that a UE does not incorrectly usean identity of another UE. For example, contention resolution 1250 maybe based on C-RNTI on PDCCH or a UE contention resolution identity onDL-SCH. For example, if a base station assigns a C-RNTI to a UE, the UEmay perform contention resolution 1250 based on a reception of a PDCCHtransmission that is addressed to the C-RNTI. In response to detectionof a C-RNTI on a PDCCH, a UE may consider contention resolution 1250successful and may consider a random access procedure successfullycompleted. If a UE has no valid C-RNTI, a contention resolution may beaddressed by employing a TC-RNTI. For example, if a MAC PDU issuccessfully decoded and a MAC PDU comprises a UE contention resolutionidentity MAC CE that matches the CCCH SDU transmitted in Msg3 1250, a UEmay consider the contention resolution 1250 successful and may considerthe random access procedure successfully completed.

FIG. 13 is an example structure for MAC entities as per an aspect of anembodiment. In an example, a wireless device may be configured tooperate in a multi-connectivity mode. A wireless device in RRC_CONNECTEDwith multiple RX/TX may be configured to utilize radio resourcesprovided by multiple schedulers located in a plurality of base stations.The plurality of base stations may be connected via a non-ideal or idealbackhaul over the Xn interface. In an example, a base station in aplurality of base stations may act as a master base station or as asecondary base station. A wireless device may be connected to one masterbase station and one or more secondary base stations. A wireless devicemay be configured with multiple MAC entities, e.g. one MAC entity formaster base station, and one or more other MAC entities for secondarybase station(s). In an example, a configured set of serving cells for awireless device may comprise two subsets: an MCG comprising servingcells of a master base station, and one or more SCGs comprising servingcells of a secondary base station(s). FIG. 13 illustrates an examplestructure for MAC entities when MCG and SCG are configured for awireless device.

In an example, at least one cell in a SCG may have a configured UL CC,wherein a cell of at least one cell may be called PSCell or PCell ofSCG, or sometimes may be simply called PCell. A PSCell may be configuredwith PUCCH resources. In an example, when a SCG is configured, there maybe at least one SCG bearer or one split bearer. In an example, upondetection of a physical layer problem or a random access problem on aPSCell, or upon reaching a number of RLC retransmissions associated withthe SCG, or upon detection of an access problem on a PSCell during a SCGaddition or a SCG change: an RRC connection re-establishment proceduremay not be triggered, UL transmissions towards cells of an SCG may bestopped, a master base station may be informed by a UE of a SCG failuretype and DL data transfer over a master base station may be maintained.

In an example, a MAC sublayer may provide services such as data transferand radio resource allocation to upper layers (e.g. 1310 or 1320). A MACsublayer may comprise a plurality of MAC entities (e.g. 1350 and 1360).A MAC sublayer may provide data transfer services on logical channels.To accommodate different kinds of data transfer services, multiple typesof logical channels may be defined. A logical channel may supporttransfer of a particular type of information. A logical channel type maybe defined by what type of information (e.g., control or data) istransferred. For example, BCCH, PCCH, CCCH and DCCH may be controlchannels and DTCH may be a traffic channel. In an example, a first MACentity (e.g. 1310) may provide services on PCCH, BCCH, CCCH, DCCH, DTCHand MAC control elements. In an example, a second MAC entity (e.g. 1320)may provide services on BCCH, DCCH, DTCH and MAC control elements.

A MAC sublayer may expect from a physical layer (e.g. 1330 or 1340)services such as data transfer services, signaling of HARQ feedback,signaling of scheduling request or measurements (e.g. CQI). In anexample, in dual connectivity, two MAC entities may be configured for awireless device: one for MCG and one for SCG. A MAC entity of wirelessdevice may handle a plurality of transport channels. In an example, afirst MAC entity may handle first transport channels comprising a PCCHof MCG, a first BCH of MCG, one or more first DL-SCHs of MCG, one ormore first UL-SCHs of MCG and one or more first RACHs of MCG. In anexample, a second MAC entity may handle second transport channelscomprising a second BCH of SCG, one or more second DL-SCHs of SCG, oneor more second UL-SCHs of SCG and one or more second RACHs of SCG.

In an example, if a MAC entity is configured with one or more SCells,there may be multiple DL-SCHs and there may be multiple UL-SCHs as wellas multiple RACHs per MAC entity. In an example, there may be one DL-SCHand UL-SCH on a SpCell. In an example, there may be one DL-SCH, zero orone UL-SCH and zero or one RACH for an SCell. A DL-SCH may supportreceptions using different numerologies and/or TTI duration within a MACentity. A UL-SCH may also support transmissions using differentnumerologies and/or TTI duration within the MAC entity.

In an example, a MAC sublayer may support different functions and maycontrol these functions with a control (e.g. 1355 or 1365) element.Functions performed by a MAC entity may comprise mapping between logicalchannels and transport channels (e.g., in uplink or downlink),multiplexing (e.g. 1352 or 1362) of MAC SDUs from one or differentlogical channels onto transport blocks (TB) to be delivered to thephysical layer on transport channels (e.g., in uplink), demultiplexing(e.g. 1352 or 1362) of MAC SDUs to one or different logical channelsfrom transport blocks (TB) delivered from the physical layer ontransport channels (e.g., in downlink), scheduling information reporting(e.g., in uplink), error correction through HARQ in uplink or downlink(e.g. 1363), and logical channel prioritization in uplink (e.g. 1351 or1361). A MAC entity may handle a random access process (e.g. 1354 or1364).

FIG. 14 is an example diagram of a RAN architecture comprising one ormore base stations. In an example, a protocol stack (e.g. RRC, SDAP,PDCP, RLC, MAC, and PHY) may be supported at a node. A base station(e.g. gNB 120A or 120B) may comprise a base station central unit (CU)(e.g. gNB-CU 1420A or 1420B) and at least one base station distributedunit (DU) (e.g. gNB-DU 1430A, 1430B, 1430C, or 1430D) if a functionalsplit is configured. Upper protocol layers of a base station may belocated in a base station CU, and lower layers of the base station maybe located in the base station DUs. An F1 interface (e.g. CU-DUinterface) connecting a base station CU and base station DUs may be anideal or non-ideal backhaul. F1-C may provide a control plane connectionover an F1 interface, and F1-U may provide a user plane connection overthe F1 interface. In an example, an Xn interface may be configuredbetween base station CUs.

In an example, a base station CU may comprise an RRC function, an SDAPlayer, and a PDCP layer, and base station DUs may comprise an RLC layer,a MAC layer, and a PHY layer. In an example, various functional splitoptions between a base station CU and base station DUs may be possibleby locating different combinations of upper protocol layers (RANfunctions) in a base station CU and different combinations of lowerprotocol layers (RAN functions) in base station DUs. A functional splitmay support flexibility to move protocol layers between a base stationCU and base station DUs depending on service requirements and/or networkenvironments.

In an example, functional split options may be configured per basestation, per base station CU, per base station DU, per UE, per bearer,per slice, or with other granularities. In per base station CU split, abase station CU may have a fixed split option, and base station DUs maybe configured to match a split option of a base station CU. In per basestation DU split, a base station DU may be configured with a differentsplit option, and a base station CU may provide different split optionsfor different base station DUs. In per UE split, a base station (basestation CU and at least one base station DUs) may provide differentsplit options for different wireless devices. In per bearer split,different split options may be utilized for different bearers. In perslice splice, different split options may be applied for differentslices.

FIG. 15 is an example diagram showing RRC state transitions of awireless device. In an example, a wireless device may be in at least oneRRC state among an RRC connected state (e.g. RRC Connected 1530,RRC_Connected), an RRC idle state (e.g. RRC Idle 1510, RRC_Idle), and/oran RRC inactive state (e.g. RRC Inactive 1520, RRC_Inactive). In anexample, in an RRC connected state, a wireless device may have at leastone RRC connection with at least one base station (e.g. gNB and/or eNB),which may have a UE context of the wireless device. A UE context (e.g. awireless device context) may comprise at least one of an access stratumcontext, one or more radio link configuration parameters, bearer (e.g.data radio bearer (DRB), signaling radio bearer (SRB), logical channel,QoS flow, PDU session, and/or the like) configuration information,security information, PHY/MAC/RLC/PDCP/SDAP layer configurationinformation, and/or the like configuration information for a wirelessdevice. In an example, in an RRC idle state, a wireless device may nothave an RRC connection with a base station, and a UE context of awireless device may not be stored in a base station. In an example, inan RRC inactive state, a wireless device may not have an RRC connectionwith a base station. A UE context of a wireless device may be stored ina base station, which may be called as an anchor base station (e.g. lastserving base station).

In an example, a wireless device may transition a UE RRC state betweenan RRC idle state and an RRC connected state in both ways (e.g.connection release 1540 or connection establishment 1550; or connectionreestablishment) and/or between an RRC inactive state and an RRCconnected state in both ways (e.g. connection inactivation 1570 orconnection resume 1580). In an example, a wireless device may transitionits RRC state from an RRC inactive state to an RRC idle state (e.g.connection release 1560).

In an example, an anchor base station may be a base station that maykeep a UE context (a wireless device context) of a wireless device atleast during a time period that a wireless device stays in a RANnotification area (RNA) of an anchor base station, and/or that awireless device stays in an RRC inactive state. In an example, an anchorbase station may be a base station that a wireless device in an RRCinactive state was lastly connected to in a latest RRC connected stateor that a wireless device lastly performed an RNA update procedure in.In an example, an RNA may comprise one or more cells operated by one ormore base stations. In an example, a base station may belong to one ormore RNAs. In an example, a cell may belong to one or more RNAs.

In an example, a wireless device may transition a UE RRC state from anRRC connected state to an RRC inactive state in a base station. Awireless device may receive RNA information from the base station. RNAinformation may comprise at least one of an RNA identifier, one or morecell identifiers of one or more cells of an RNA, a base stationidentifier, an IP address of the base station, an AS context identifierof the wireless device, a resume identifier, and/or the like.

In an example, an anchor base station may broadcast a message (e.g. RANpaging message) to base stations of an RNA to reach to a wireless devicein an RRC inactive state, and/or the base stations receiving the messagefrom the anchor base station may broadcast and/or multicast anothermessage (e.g. paging message) to wireless devices in their coveragearea, cell coverage area, and/or beam coverage area associated with theRNA through an air interface.

In an example, when a wireless device in an RRC inactive state movesinto a new RNA, the wireless device may perform an RNA update (RNAU)procedure, which may comprise a random access procedure by the wirelessdevice and/or a UE context retrieve procedure. A UE context retrieve maycomprise: receiving, by a base station from a wireless device, a randomaccess preamble; and fetching, by a base station, a UE context of thewireless device from an old anchor base station. Fetching may comprise:sending a retrieve UE context request message comprising a resumeidentifier to the old anchor base station and receiving a retrieve UEcontext response message comprising the UE context of the wirelessdevice from the old anchor base station.

In an example embodiment, a wireless device in an RRC inactive state mayselect a cell to camp on based on at least a on measurement results forone or more cells, a cell where a wireless device may monitor an RNApaging message and/or a core network paging message from a base station.In an example, a wireless device in an RRC inactive state may select acell to perform a random access procedure to resume an RRC connectionand/or to transmit one or more packets to a base station (e.g. to anetwork). In an example, if a cell selected belongs to a different RNAfrom an RNA for a wireless device in an RRC inactive state, the wirelessdevice may initiate a random access procedure to perform an RNA updateprocedure. In an example, if a wireless device in an RRC inactive statehas one or more packets, in a buffer, to transmit to a network, thewireless device may initiate a random access procedure to transmit oneor more packets to a base station of a cell that the wireless deviceselects. A random access procedure may be performed with two messages(e.g. 2 stage random access) and/or four messages (e.g. 4 stage randomaccess) between the wireless device and the base station.

In an example embodiment, a base station receiving one or more uplinkpackets from a wireless device in an RRC inactive state may fetch a UEcontext of a wireless device by transmitting a retrieve UE contextrequest message for the wireless device to an anchor base station of thewireless device based on at least one of an AS context identifier, anRNA identifier, a base station identifier, a resume identifier, and/or acell identifier received from the wireless device. In response tofetching a UE context, a base station may transmit a path switch requestfor a wireless device to a core network entity (e.g. AMF, MME, and/orthe like). A core network entity may update a downlink tunnel endpointidentifier for one or more bearers established for the wireless devicebetween a user plane core network entity (e.g. UPF, S-GW, and/or thelike) and a RAN node (e.g. the base station), e.g. changing a downlinktunnel endpoint identifier from an address of the anchor base station toan address of the base station.

In a legacy system, a wireless device that experiences a connectionfailure (for example, a radio link failure, a handover failure, and/orthe like) provides, for a base station, a radio link failure (RLF)report comprising information of the connection failure. The informationof the connection failure may comprise configuration parameters and/ormeasurement results of a failed cell. Based on the information of theconnection failure, the base station may configure radio resourceparameters for one or more wireless devices (for example, to reduceconnection failure issues of serving wireless devices). In animplementation of existing technologies, when a wireless deviceexperiences a connection failure due to improper beam failure recoveryconfigurations, a base station may consider and update cell levelconfiguration parameters (for example, parameters for whole beams of afailed cell and/or per-cell parameters). Considering cell levelconfiguration parameters, when a certain beam failure recoveryconfiguration or a certain beam has a problem, is inefficient. Theinefficient cell parameter reconfiguration may decrease efficientresource utilization and radio connection reliability of wirelessdevices. Existing technologies to handle connection failure issues thatoccur due to a beam failure need enhancements.

Example embodiments may enhance a radio link failure report by providinginformation of a beam failure recovery failure, so that a base stationis able to identify a cause (for example, improper configurations for abeam failure recovery procedure) of wireless device's connectionfailure. A base station may employ information of a beam failurerecovery failure to update radio configuration parameters to improveuplink/downlink connections.

In existing connection failure report signaling (e.g. RLF report via anRRC message), a wireless device (e.g. UE) provides failed cellinformation, measurement information at connection failure timing, radioconfiguration parameters, and/or connection failure cause information(e.g. T310 expiry, random access problem, RLC maximum number ofretransmission, T312 expiry). A wireless device may further transmit atime of connection failure, carrier frequency information of a failedcell, and/or bearer configuration information at connection failuretiming. A base station receiving a connection failure report mayconfigure radio resource configuration parameters based on theconnection failure report. Implementation of existing connection failurereport may result in, for example, inefficient radio resourceconfigurations, inefficient mobility parameter setting, or increasedcall dropping when a connection failure occurs due to a beam failurerecovery request failure. For example, a base station in implementationof existing connection failure report may result in inefficient resourceusage, increased handover failures, increased connection failure, ormore frequent call dropping by configuring inefficient radio resourceconfiguration parameters when a beam failure recovery request failurecauses a connection failure. A beam failure recovery report failureintroduces a need for further enhancement in connection failure reportmechanism. Example embodiments enhance connection failure reports ofwireless devices when a beam failure recovery request is failed. Exampleembodiments enhance connection failure report mechanism when aconnection failure occur due to a beam failure recovery request failure.

In an example embodiment, a wireless device may experience a connectionfailure (e.g. radio link failure (RLF) and/or handover failure (HOF)) ata cell of a base station (e.g. gNB, eNB). The connection failure may becaused because of a failure of a beam failure recovery request procedureand/or because of expiration of a beam failure recovery timer. Awireless device may report a connection failure to the base station orother base station to which the wireless device (re)establishes a radioresource control (RRC) connection. The wireless device may send, to thefirst base station, a connection failure report comprising an RLF causeindicating that the connection failure is because of a failure of a beamfailure recovery request procedure and/or because of expiration of abeam failure recovery timer. If the wireless device sends the connectionfailure report to the other base station from the base station where theconnection failure occurs, the other base station may send the RLF causeto the base station. The base station receiving the RLF cause for theconnection failure may determine one or more radio resourceconfiguration parameters for one or more wireless devices based on theRLF cause. Example embodiments implement new mechanism to enhance radioresource configuration of a base station when a beam failure recoveryrequest failure causes a connection failure. Example embodiments improvea connection failure report mechanism when a beam failure recoveryrequest failure causes a connection failure. Example embodiments improveresource usage efficiency, handover efficiency, connection efficiency,or call efficiency by enabling a base station to configure radioresource configuration parameters in response to a connection failurecaused due to a beam failure recovery request failure.

Connection Failure

In an example, a wireless device in an RRC connected state mayexperience (and/or determine) a connection failure from at least onecell of a base station. A connection failure may comprise a radio linkfailure (RLF) and/or a handover failure (HOF).

In an example, a wireless device may determine an RLF when one offollowing criteria are met: expiry of a timer started after indicationof radio problems (e.g. out of sync) from a physical layer (if radioproblems are recovered before the timer is expired, the UE may stop thetimer); random access procedure failure; RLC failure (e.g. a number ofretransmission is over a threshold); and/or the like. In an example,after the RLF is declared, the wireless device may: stay in anRRC_CONNECTED state (e.g. RRC connected state); select a suitable celland initiate RRC re-establishment; enter an RRC_IDLE state (e.g. RRCidle state) if a suitable cell wasn't found within a certain time afterthe RLF was declared; stay at an RRC_INACTIVE state (e.g. RRC inactivestate) if a suitable cell wasn't found within a certain time after theRLF was declared; and/or the like.

In an example, a behavior of a wireless device associated with the RLFmay comprise two phases. A first phase may be started upon a radioproblem detection; may lead to the RLF detection; may not initiate a UEbased mobility; may be based on a timer (e.g. T1) or other criteria(e.g. counting); and/or the like. A second phase may be started upon theRLF or the HOF; may leads to an RRC idle state of the wireless device;may initiate a UE based mobility; may be based on a timer (e.g. T2);and/or the like. In an example, the wireless device in a normaloperation of an RRC connected state may experience the first phasecomprising the radio problem detection and no recovery during the T1,and/or may experience the second phase comprising no recovery during theT2. The second phase may be followed by an RRC idle state (e.g. thewireless device may go to an RRC idle state). During the normaloperation, the first phase, and/or the second phase, the wireless devicemay be considered as being in an RRC connected state. In an example, theRLF may be considered as occurring between the first phase and thesecond phase (e.g. at an ending time of the first phase and/or at thestarting time of the second phase).

In an example, upon detecting physical layer problems for a PCell, i.e.upon receiving N310 consecutive out-of-sync indications from lowerlayers, a wireless device may start a timer, T310. Upon receiving N311consecutive in-sync indications from lower layers for the PCell, and/orupon triggering a handover procedure and upon initiating a connectionre-establishment procedure, a wireless device may stop T310. In anexample, when a timer, T310, is expired, if security is not activated, awireless device may go to RRC_IDLE state; and/or if security isactivated, a wireless device may initiate a connection re-establishmentprocedure.

In an example, upon initiating an RRC connection re-establishmentprocedure, a wireless device may start a timer, T311. Upon selecting asuitable cell of LTE/5G/another RAT, a wireless device may stop T311. IfT311 is expired, a wireless device may enter an RRC_IDLE state.

In an example, a wireless device may detect the HOF that may occur dueto a too early handover, a too late handover, a handover to wrong cell,and/or the like. In case of the too early handover, a radio link failuremay occur shortly after a successful handover from a source cell to atarget cell, and/or a handover failure may occur during a handoverprocedure. In case of the too early handover, the wireless device mayattempt to reestablish a radio link connection in the source cell. Incase of the too late handover, a radio link failure may occur after thewireless device may stay for a long period of time in a cell (e.g. aradio link failure may occur because a serving base station may notinitiate a handover for the wireless device when a radio link quality isnot good enough to serve the wireless device in a current cell.), and/orthe wireless device may attempt to reestablish a radio link connectionin a different cell. In case of the handover to wrong cell, a radio linkfailure may occur shortly after a successful handover from a source cellto a target cell, and/or a handover failure may occur during a handoverprocedure. In case of the handover to wrong cell, the UE may attempt toreestablish a radio link connection in a cell other than the source celland the target cell. In an example, the “successful handover” may referto wireless device's state of a successful completion of a random access(RA) procedure.

In an example, to resolve a problem of a connection failure (e.g. RLFand/or HOF), a wireless device and/or a network (e.g. a base station, abase station CU, a base station DU, a gNB, an eNB, a core network,and/or the like) may trigger one or more of following functions: adetection of the connection failure after an RRC reestablishmentattempt; a detection of the connection failure after an RRC connectionsetup; a retrieval of information needed for problem analysis; and/orthe like. Triggering of each of the functions may be optional, and/ormay depend on situation and/or implementation.

Beam Configurations

A UE may be configured, for a serving cell, with a set of periodicCSI-RS resource configuration indexes by higher layer parameter, e.g.Beam-Failure-Detection-RS-ResourceConfig, and with a set of CSI-RSresource configuration indexes and/or SS/PBCH block indexes by higherlayer parameter, e.g. Candidate-Beam-RS-List, for radio link qualitymeasurements on the serving cell. If the UE is not provided with higherlayer parameter, e.g. Beam-Failure-Detection-RS-ResourceConfig, the UEmay determine to include SS/PBCH blocks and/or periodic CSI-RSconfigurations with same values for higher layer parameter, e.g.TCI-StatesPDCCH, as for control resource sets that the UE may beconfigured for monitoring PDCCH.

A physical layer of the UE may assess a radio link quality according toa set of resource configurations against the threshold Q_(out, LR). Thethreshold Q_(out, LR) may correspond to a default value of higher layerparameters, e.g. RLM-IS-OOS-thresholdConfig and/orBeam-failure-candidate-beam-threshold, respectively. For the set, the UEmay assess a radio link quality according to periodic CSI-RS resourceconfigurations and/or SS/PBCH blocks that may be quasi co-located, witha DM-RS of PDCCH receptions DM-RS monitored by the UE. The UE may applythe configured Q_(in, LR) threshold for periodic CSI-RS resourceconfigurations. The UE may apply the Q_(out, LR) threshold for SS/PBCHblocks after scaling a SS/PBCH block transmission power with a valueprovided by higher layer parameter, e.g. Pc_SS.

The physical layer in the UE may, in slots where a radio link qualityaccording to the set may be assessed, provide an indication to higherlayers when a radio link quality for corresponding resourceconfigurations in the set that the UE may use to assess the radio linkquality is worse than the threshold Q_(out, LR). The UE may provide tohigher layers information identifying a periodic CSI-RS configurationindex or SS/PBCH block index from the set.

A UE may be configured with one control resource set (CORESET) by higherlayer parameter, e.g. Beam-failure-Recovery-Response-CORESET. The UE mayreceive from higher layers, by parameter, e.g.Beam-failure-recovery-request-RACH-Resource, a configuration for a PRACHtransmission. After 4 slots from the slot of the PRACH transmission, theUE may monitor PDCCH for a DCI format with CRC scrambled by C-RNTI,within a window configured by higher layer parameter, e.g.Beam-failure-recovery-request-window, and/or may receive PDSCH accordingto an antenna port quasi co-location associated with periodic CSI-RSconfiguration or SS/PBCH block with index in set, in the CORESETconfigured by higher layer parameter, e.g.Beam-failure-Recovery-Response-CORESET.

In an example, a beam failure recovery request procedure may be used forindicating to a serving gNB of a new synchronization signal block (SSB)or channel state information reference signal (CSI-RS) when beam failureis detected on a serving SSB(s) and/or CSI-RS(s). Beam failure may bedetected by lower layers of a wireless device and/or indicated to a MACentity of the wireless device.

In an example, if a MAC entity receives beam failure indication fromlower layers (e.g. physical layer), the MAC entity may start a beamfailure recover timer (e.g. beamFailureRecoveryTimer), and/or mayinitiate a random access procedure on a SpCell. If the beam failurerecovery timer expires, the MAC entity may indicate beam failurerecovery request failure to upper layers (e.g. RRC layer). In anexample, the MAC entity receives downlink assignment and/or uplink granton a PDCCH addressed for a C-RNTI, the MAC entity may stop/reset thebeam failure recover timer and/or may consider a beam failure recoveryrequest procedure successfully completed.

A NR (New Radio) may support both single beam and multi-beam operations.In a multi-beam system, gNB may need a downlink beam sweep to providecoverage for DL synchronization signals (SSs) and common controlchannels. To enable UEs to access the cell, the UEs may need the similarsweep for UL direction as well.

In the single beam scenarios, the network may configure time-repetitionwithin one synchronization signal (SS) block, which may comprise atleast PSS (Primary synchronization signal), SSS (Secondarysynchronization signal), and PBCH (Physical broadcast channel), in awide beam. In multi-beam scenarios, the network may configure at leastsome of these signals and physical channels (e.g. SS Block) in multiplebeams such that a UE identifies at least OFDM symbol index, slot indexin a radio frame and radio frame number from an SS block.

An RRC_INACTIVE or RRC_IDLE UE may need to assume that an SS Block mayform an SS Block Set and, an SS Block Set Burst, having a givenperiodicity. In multi-beam scenarios, the SS Block may be transmitted inmultiple beams, together forming an SS Burst. If multiple SS Bursts areneeded to transmit beams, these SS Bursts together may form an SS BurstSet. Top: Time-repetition within one SS Burst in a wide beam. Middle:Beam-sweeping of a small number of beams using one SS Burst in the SSBurst Set. Bottom: Beam-sweeping of a larger number of beams using morethan one SS Burst in the SS Burst Set to form a complete sweep.

In the multi-beam scenario, for the same cell, PSS/SSS/PBCH may berepeated to support cell selection/reselection and initial accessprocedures. There may be some differences in the conveyed PRACHconfiguration implied by the TSS (Tertiary synchronization signal) on abeam basis within an SS Burst. Under the assumption that PBCH carriesthe PRACH configuration, a gNB may broadcast PRACH configurationspossibly per beam where the TSS may be utilized to imply the PRACHconfiguration differences.

In an example, the base station may transmit to a wireless device one ormore messages comprising configuration parameters of one or more cells.The configuration parameters may comprise parameters of a plurality ofCSI-RS signal format and/or resources. Configuration parameters of aCSI-RS may comprise one or more parameters indicating CSI-RSperiodicity, one or more parameters indicating CSI-RS subcarriers (e.g.resource elements), one or more parameters indicating CSI-RS sequence,and/or other parameters. Some of the parameters may be combined into oneor more parameters. A plurality of CSI-RS signals may be configured. Inan example, the one or more message may indicate the correspondencebetween SS blocks and CSI-RS signals. The one or more messages may beRRC connection setup message, RRC connection resume message, and/or RRCconnection reconfiguration message. In an example, a UE in RRC-Idle modemay not be configured with CSI-RS signals and may receive SS blocks andmay measure a pathloss based on SS signals. A UE in RRC-connected mode,may be configured with CSI-RS signals and may be measure pathloss basedon CSI-RS signals. In an example, a UE in RRC inactive mode may measurethe pathloss based on SS blocks, e.g. when the UE moves to a differentbase station that has a different CSI-RS configuration compared with theanchor base station.

In a multi-beam system, a NR may configure different types of PRACHresources that may be associated with SS blocks and/or DL beams. In NR,a PRACH transmission occasion may be defined as the time-frequencyresource on which a UE transmits a preamble using the configured PRACHpreamble format with a single particular Tx beam and for which gNBperforms PRACH preamble detection. One PRACH occasion may be used tocover the beam non-correspondence case. gNB may perform RX sweep duringPRACH occasion as UE TX beam alignment is fixed during single occasion.A PRACH burst may mean a set of PRACH occasions allocated consecutivelyin time domain, and a PRACH burst set may mean a set of PRACH bursts toenable full RX sweep.

There may be an association between SS blocks (DL signal/channel) andPRACH occasion and a subset of PRACH preamble resources. One PRACHoccasion may comprise a set of preambles. In multi beam operation, thegNB may need to know which beam or set of beams it may use to send RARand the preambles may be used to indicate that. NR may configurefollowing partitioning and mappings in multi beam operation:

The timing from SS block to the PRACH resource may be indicated in theMIB. In an example, different TSS may be used for different timings suchthat the detected sequence within TSS indicates the PRACH resource. ThisPRACH configuration may be specified as a timing relative to the SSblock, and may be given as a combination of the payload in the MIB andanother broadcasted system information.

Association between SS block and a subset of RACH resources and/or asubset of preamble indices may be configured so that TRP may identifythe best DL beam for a UE according to resource location or preambleindex of received preamble. An association may be independent and atleast either a subset of RACH resources or subset of preamble indicesmay not be allowed to be associated with multiple SS blocks.

PRACH resources may be partitioned on SS-blocks basis in multiple beamsoperation. There may be one to one and/or many to one mapping betweenSS-blocks and PRACH occasions. UE may detect SS-block based on DLsynchronization signals and differentiate SS-blocks based on the timeindex. With one-to-one mapping of beam or beams used to transmitSS-block and a specific PRACH occasion, the transmission of PRACHpreamble resource may be an indication informed by a UE to gNB of thepreferred SS-block. This way the PRACH preamble resources of singlePRACH occasion may correspond to specific SS-block and mapping may bedone based on the SS-block index. There may be one to one mappingbetween an SS-block beam and a PRACH occasion. There may not be suchmapping for the SS-block periodicity and RACH occasion periodicity.

Depending on the gNB capability (e.g. the used beamformingarchitecture), there may not be one to one mapping between singleSS-block and single RACH occasion. In case beam or beams used fortransmitting SS-block and receiving during RACH occasion do notcorrespond directly, e.g., gNB may form receive beams that covermultiple SS-blocks beams, the preambles of PRACH occasion may be dividedbetween the different SS-blocks in a manner that a subset of PRACHpreambles map to specific SS-block.

With beam-specific PRACH resources, a gNB DL TX beam may be associatedwith a subset of preambles. The beam specific PRACH preambles resourcesmay be associated with DL TX beams that are identified by periodicalbeam and cell specific CSI-RS for L3 Mobility (same signals may be usedfor L2 beam management/intra-cell mobility as well). A UE may detect thebeams without RRC configuration, e.g., reading the beam configurationfrom minimum SI (MIB/SIB).

The PRACH resource mapping to specific beams may use SS-blockassociation. Specific beams may be associated with the beams used fortransmitting SS-block. gNB may transmit SS-block using one or multiplebeams (in case of analogue/hybrid beamforming), but individual beams maynot be detected. From the UE perspective, this is a single beamtransmission. gNB may transmit CSI-RS (for Mobility) using individualbeams associated with specific SS-block. A UE may detect individualbeams based on the CSI-RS.

PRACH occasion may be mapped to corresponding SS-block, and a set ofPRACH preambles may be divided between beams. Similar to mapping ofmultiple SS-blocks to single PRACH occasion, multiple beams of anSS-block may be mapped to at least one PRACH occasion.

If a PRACH occasion is configured with k preambles, and a PRACH occasionis configured to be SS-block specific, the whole set of preambles may beused to indicate the specific SS-block. In this case, there may be NPRACH occasions corresponding to N SS-blocks.

If multiple SS-blocks are mapped to single PRACH occasion, then thepreambles may be divided between SS-blocks and depending on the numberof SS-blocks, the available preambles per SS-block may be K/N (Kpreambles, N SS-blocks).

If K SS-block specific preambles are divided between CSI-RS beams in thecorresponding PRACH occasions, the number of available preambles perbeam may be determined by the K preambles/number of beams.

If the preambles are partitioned in SS-block specific manner, the UE mayindicate preferred SS-block but not the preferred individual DL TX beamto gNB.

The network may configure mapping/partitioning PRACH preamble resourcesto SS-blocks and/or to individual beams. A UE may determine the usedpartitioning of PRACH preambles, as much as possible, e.g. based on thePRACH configuration.

Beam-specific PRACH configurations may be configurable when a gNB usesanalog RX beamforming. In that case, when a UE sends, for example, apreamble in a beam-specific time/frequency slot associated with one ormultiple SS Block transmissions, then the gNB may use the appropriate RXbeamforming when receiving the preamble in that time/frequency slot anduse the corresponding DL beam when transmitting the RAR. Hence,beam-specific PRACH configurations may allow the gNB to direct its Rxbeamforming in the direction of the same beam when monitoring theassociated PRACH resources.

In the multi-beam RACH scenario, thanks to the mapping between DL SSbeams and PRACH configuration, e.g. time/frequency slot and possiblypreamble partitioning, a UE may be under the coverage of a given DL beamor at least a subset of them in a cell. That may enable the network tosend a RAR in this best DL beam and/or perform a more optimized beamsweeping procedure e.g. not transmitting the same RAR message inpossible beams (e.g. transmitting the RAR in a single beam as in thefigure below).

NR may support the contention-free scenarios in a way to provide adedicated RACH resource for the preamble transmission as in LTE forhandover, DL data arrival, positioning and obtaining timing advancealignment for a secondary TAG. For the handover case, a UE may beconfigured to measure on one or more SS blocks or other RS in aneighboring cell. If one of the neighboring cell SS-block measurementstriggers a handover request, the source gNB may signal a preferred beamindex in a handover request to the target gNB. The target gNB in turnmay provide a beam-specific dedicated RACH resource (including preamble)in the handover command. In an example, the target gNB may provide a setof dedicated resources e.g. one for at least one SS-block in thehandover command. The UE then may transmit Msg1 using the dedicatedpreamble corresponding to the preferred DL beam in the target cell.

In an example, a cell may be operated with one or more beams employing amulti-antenna system. A beam may have a spatial direction, and/or maycover a part of a cell coverage area. A combination of one or more beamspatial areas may form a cell coverage. In an example, a beamtransmitting a synchronization signal and/or receiving a signal from awireless device may be swept over a cell coverage area in apredetermined way. A synchronization signal index, a synchronizationsignal scheduling information, and/or a synchronization signal sequenceinformation may be used to identify a swept beam. A swept beam maybroadcast one or more control information comprising at least one of asystem information, a master information, a PDCCH, a PRACH resource, arandom access preamble information, a synchronization signal, areference signal, and/or the like. In an example, a beam may transmit areference signal (e.g. CSI-RS). A beam may be also identified by areference signal (e.g. CSI-RS, DM-RS, and the like) index, a referencesignal scheduling information, and/or a reference signal sequenceinformation.

In an example, one or more beams may be managed via a set of L1/L2procedures to acquire and maintain a set of TRP(s)(TransmissionReception Point) and/or UE beams that may be used for DL and ULtransmission/reception, which may include at least following aspects:Beam determination (for TRP(s) or UE to select of its own Tx/Rxbeam(s)), Beam measurement (for TRP(s) or UE to measure characteristicsof received beamformed signals), Beam reporting (for UE to reportinformation of beamformed signal(s) based on beam measurement), and/orBeam sweeping (operation of covering a spatial area, with beamstransmitted and/or received during a time interval in a predeterminedway).

In an example, the followings may be defined as Tx/Rx beamcorrespondence at TRP and UE. Tx/Rx beam correspondence at TRP holds ifat least one of the following is satisfied: TRP may be able to determinea TRP Rx beam for the uplink reception based on UE's downlinkmeasurement on TRP's one or more Tx beams; and/or TRP may be able todetermine a TRP Tx beam for the downlink transmission based on TRP'suplink measurement on TRP's one or more Rx beams. Tx/Rx beamcorrespondence at UE may hold if at least one of the following issatisfied: UE may be able to determine a UE Tx beam for the uplinktransmission based on UE's downlink measurement on UE's one or more Rxbeams; UE may be able to determine a UE Rx beam for the downlinkreception based on TRP's indication based on uplink measurement on UE'sone or more Tx beams; and/or capability indication of UE beamcorrespondence related information to TRP may be supported.

In an example, the following DL L1/L2 beam management procedures (e.g.P-1, P-2, and P-3) may be supported within one or multiple TRPs. P-1 maybe used to enable UE measurement on different TRP Tx beams to supportselection of TRP Tx beams/UE Rx beam(s). For beamforming at TRP, ittypically may include a intra/inter-TRP Tx beam sweep from a set ofdifferent beams. For beamforming at UE, it may include a UE Rx beamsweep from a set of different beams. P-2 may be used to enable UEmeasurement on different TRP Tx beams to possibly change inter/intra-TRPTx beam(s). From a possibly smaller set of beams for beam refinementthan in P-1. P-2 may be a special case of P-1. P-3 may be used to enableUE measurement on the same TRP Tx beam to change UE Rx beam in the caseUE uses beamforming. At least network triggered aperiodic beam reportingmay be supported under P-1, P-2, and P-3 related operations.

In an example, UE measurement based on RS for beam management (at leastCSI-RS) may be composed of K (=total number of configured beams) beams,and/or UE may report measurement results of N selected Tx beams, where Nmay not be necessarily fixed number. The procedure based on RS formobility purpose may be not precluded. Reporting information may atleast include measurement quantities for N beam (s) and informationindicating N DL Tx beam(s), if N <K. Specifically, when a UE isconfigured with K′>1 non-zero power (NZP) CSI-RS resources, a UE mayreport N′ CRIs (CSI-RS Resource Indicator). A UE may be configured withthe following high layer parameters for beam management. N≥1 reportingsettings, M≥1 resource settings: the links between reporting settingsand resource settings may be configured in the agreed CSI measurementsetting; CSI-RS based P-1 & P-2 may be supported with resource andreporting settings; and/or P-3 may be supported with or withoutreporting setting. A reporting setting at least including: informationindicating selected beam(s); L1 measurement reporting; time-domainbehavior, e.g. aperiodic, periodic, semi-persistent; and/orfrequency-granularity if multiple frequency granularities are supported.A resource setting at least including: time-domain behavior, e.g.aperiodic, periodic, semi-persistent; RS type, e.g. NZP CSI-RS at least;at least one CSI-RS resource set, with each CSI-RS resource set havingK≥1 CSI-RS resources (Some parameters of K CSI-RS resources may be thesame, e.g. port number, time-domain behavior, density and periodicity ifany).

In an example, a beam reporting may be supported at least based on analternative 1 as follow. UE may report information about TRP Tx Beam(s)that may be received using selected UE Rx beam set(s) where a Rx beamset may refer to a set of UE Rx beams that may be used for receiving aDL signal. It may be UE implementation issues on how to construct the Rxbeam set. One example may be that each of Rx beam in a UE Rx beam setmay correspond to a selected Rx beam in each panel. For UEs with morethan one UE Rx beam sets, the UE may report TRP Tx Beam(s) and anidentifier of the associated UE Rx beam set per reported TX beam(s).Different TRP Tx beams reported for the same Rx beam set may be receivedsimultaneously at the UE. Different TRP TX beams reported for differentUE Rx beam set may not be possible to be received simultaneously at theUE.

In an example, a beam reporting may be supported at least based on analternative 2 as follow. UE may report information about TRP Tx Beam(s)per UE antenna group basis where UE antenna group may refer to receiveUE antenna panel or subarray. For UEs with more than one UE antennagroup, the UE may report TRP Tx Beam(s) and an identifier of theassociated UE antenna group per reported TX beam. Different TX beamsreported for different antenna groups may be received simultaneously atthe UE. Different TX beams reported for the same UE antenna group maynot be possible to be received simultaneously at the UE.

In an example, NR may support the following beam reporting considering Lgroups where L>=1 and/or each group may refer to a Rx beam set(alternative 1) or a UE antenna group (alternative 2) depending on whichalternative may be adopted. For each group L, UE may report at least thefollowing information: information indicating group at least for somecases; measurement quantities for N_L beam(s), which may support L1 RSRPand CSI report (when CSI-RS is for CSI acquisition); and/or informationindicating N_L DL Tx beam(s) when applicable. This group based beamreporting may be configurable per UE basis. This group based beamreporting may be turned off per UE basis, e.g. when L=1 or N_L=1. Groupidentifier may not be reported when it is turned off.

In an example, NR (New Radio) may support that UE may be able to triggermechanism to recover from beam failure. Beam failure event may occurwhen the quality of beam pair link(s) of an associated control channelfalls low enough (e.g. comparison with a threshold, time-out of anassociated timer). Mechanism to recover from beam failure may betriggered when beam failure occurs. The beam pair link may be used forconvenience, and may or may not be used in specification. Network mayconfigure to UE with resources for UL transmission of signals forrecovery purpose. Configurations of resources may be supported where thebase station may be listening from all or partial directions, e.g.random access region. The UL transmission/resources to report beamfailure may be located in the same time instance as PRACH (resourcesorthogonal to PRACH resources) and/or at a time instance (configurablefor a UE) different from PRACH. Transmission of DL signal may besupported for allowing the UE to monitor the beams for identifying newpotential beams.

In an example, NR may support beam management with and withoutbeam-related indication. When beam-related indication is provided,information pertaining to UE-side beamforming/receiving procedure usedfor CSI-RS-based measurement may be indicated through QCL (QuasiCo-Location) to UE. NR may support using the same or different beams oncontrol channel and the corresponding data channel transmissions.

In an example, for NR-PDCCH transmission supporting robustness againstbeam pair link blocking, UE may be configured to monitor NR-PDCCH on Mbeam pair links simultaneously, where M>1 and the maximum value of M maydepend at least on UE capability. UE may be configured to monitorNR-PDCCH on different beam pair link(s) in different NR-PDCCH OFDMsymbols. Parameters related to UE Rx beam setting for monitoringNR-PDCCH on multiple beam pair links may be configured by higher layersignaling or MAC CE and/or considered in the search space design. Atleast, NR may support indication of spatial QCL assumption between an DLRS antenna port(s), and DL RS antenna port(s) for demodulation of DLcontrol channel. Candidate signaling methods for beam indication for aNR-PDCCH (i.e. configuration method to monitor NR-PDCCH) may be MAC CEsignaling, RRC signaling, DCI signaling, specification-transparentand/or implicit method, and combination of these signaling methods.Indication may not be needed for some cases.

In an example, for reception of unicast DL data channel, NR may supportindication of spatial QCL assumption between DL RS antenna port(s) andDMRS antenna port(s) of DL data channel. Information indicating the RSantenna port(s) may be indicated via DCI (downlink grants). Theinformation may indicate the RS antenna port(s) which may be QCL-ed withDMRS antenna port(s). Different set of DMRS antenna port(s) for the DLdata channel may be indicated as QCL with different set of RS antennaport(s). Indication may not be needed for some cases.

Example Embodiments

In an example, as shown in FIG. 16 , FIG. 17 , and/or FIG. 21 , a basestation (e.g. gNB, eNB, gNB-CU and gNB-DU, and/or the like) may serve awireless device at least via a first cell. The first cell may be a cellof the base station and/or a primary cell of the wireless device. In anexample, the base station may configure one or more secondary cells forthe wireless device. In an example, the base station may transmit a RRCmessage to the wireless device. The RRC message may comprise at leastone of RRC connection reconfiguration message, RRC connectionreestablishment message, RRC connection resume message, RRC connectionsetup message, and/or the like. The RRC message may be transmitted viathe first cell. In an example, the RRC message may comprise beamconfiguration parameters for one or more beams. The one or more beamsmay comprise one or more channel state information-reference signal(CSI-RS) beams and/or one or more synchronization signal (SS) beams.

In an example the beam configuration parameters may comprise at leastone of CSI-RS beam indexes, SS beam indexes, BRACH resourceconfigurations, BRACH preamble configuration parameters, beam based SRStransmission configuration information, beam based CSI-RS configurationparameters, beam based SS configuration parameters, beam failurerecovery timer, number of random access preamble transmissionrepetitions, beam measurement configuration parameters, and/or the like.In an example, the beam configuration parameters may comprise at leastone of beam failure detection RS resource configuration information(e.g. Beam-Failure-Detection-RS-ResourceConfig), candidate beam RS list(e.g. Candidate-Beam-RS-List) for radio link quality measurements on theserving cell, beam failure candidate beam received power threshold (e.g.Beam-failure-candidate-beam-threshold), control resource set (CORESET)information for beam failure recovery response (e.g.Beam-failure-Recovery-Response-CORESET), RACH resource for beam failurerecovery procedure (e.g. Beam-failure-recovery-request-RACH-Resource),time window information for beam failure recovery request (e.g.Beam-failure-recovery-request-window), TCI-StatesPDCCH, and/or the like.

The wireless device may measure beam quality (e.g. RSRP, RSRQ, and/orthe like) of the one or more beams, and/or may report measurementresults of beam quality of at least one of the one or more beams to thebase station. The wireless device may employ at least one of the one ormore beams to transmit transport blocks (e.g. for control signalingand/or for data signaling). The wireless device may employ at least oneof the one or more beams to receive transport blocks (e.g. for controlsignaling and/or for data signaling).

In an example, the base station may receive, from the wireless device,one or more random access (RA) preambles via at least one of the one ormore beams. In an example, the base station may transmit, to thewireless device, one or more RA response (RAR) messages via at least oneof the one or more beams. In an example, at least one of the one or morebeams may be chosen by the base station and/or the wireless devicethrough a beam refinement procedure.

In an example, the wireless device may detect a beam failure on one ormore first beams (e.g. on at least one beam of the one or more beams) ofthe first cell. The beam failure may be detected based on the beamfailure detection RS resource configuration information. The beamfailure may be detected based on a received power (e.g. RSRP, RSRQ) viathe one or more first beams. The beam failure may be detected inresponse to a received power (e.g. RSRP, RSRQ) via the one or more firstbeams equals or is smaller than a power threshold value (e.g. receivedfrom a higher layer, and/or received from the base station). The beamfailure may be detected based on a block error rate (e.g. BLER, biterror rate, BER) of one or more transport blocks received via the one ormore first beams. For example, if the block error rate equals or issmaller than a block error rate threshold value (e.g. received from ahigher layer, and/or received from the base station).

In an example, in response to detecting the beam failure, the wirelessdevice may initiate a beam failure recovery request procedure. In anexample, in response to detecting the beam failure, the wireless devicemay start a beam failure recovery timer, and/or may transmit one or morerandom access preambles (e.g. a random access preamble) to the basestation. The beam failure recovery timer may be received from the basestation via a higher layer (e.g. RRC layer) (e.g. via the beamconfiguration parameters). The transmission of the random accesspreamble may be based on the beam configuration parameters (e.g.candidate beam RS list, beam failure candidate beam received powerthreshold, control resource set (CORESET) information for beam failurerecovery response, RACH resource for beam failure recovery procedure,time window information for beam failure recovery request,TCI-StatesPDCCH, and/or the like).

In an example, in response to expiration of the beam failure recoverytimer, the wireless device may determine a beam failure recovery requestfailure. In an example, if the wireless device (e.g. MAC entity)receives downlink assignment and/or uplink grant on a PDCCH addressedfor a C-RNTI within a time duration of the beam failure recovery timer,the wireless device (e.g. the MAC entity) may stop/reset the beamfailure recover timer and/or may consider the beam failure recoveryrequest procedure successfully completed. In an example, if the wirelessdevice (e.g. MAC entity) does not receive downlink assignment and/oruplink grant on a PDCCH addressed for a C-RNTI within a time duration ofthe beam failure recovery timer, the wireless device (e.g. the MACentity) may determine a beam failure recovery request failure.

In response to determining the beam failure recovery request failure, alower layer (e.g. MAC layer, and/or physical layer) of the wirelessdevice may indicate the beam failure recovery request failure to ahigher layer (e.g. RRC layer) of the wireless device. The higher layerof the wireless device may determine a connection failure (e.g. radiolink failure (RLF) and/or handover failure (HOF)) in the first cell(e.g. a failed cell) based on the beam failure recovery request failure.In an example, the wireless device may determine a connection failure inresponse to the beam failure recovery request failure, and/or determinea connection failure after a time duration of a connection failure timer(e.g. T310 or other type of timer). The connection failure timer maystart before the beam failure recovery request failure (e.g. whenreceiving one or more out-of-sync indication, or when receiving a beamfailure indication), or may start in response to the beam failurerecovery request failure.

In an example, after determining the connection failure, the wirelessdevice may determine (select/reselect) a second cell of a first basestation based on a measurement result of the wireless device (e.g. RSRP,RSRQ). In an example, the base station (serving the first cell) may bethe first base station as shown in FIG. 17 and/or FIG. 19 , or the basestation may be different from the first base station as shown in FIG. 16and/or FIG. 18 . In an example, the second cell may be the first cell,or the second cell may be different from the first cell. In response todetermining the second cell, the wireless device may initiate a randomaccess procedure to make an RRC connection via the second cell. In anexample, the wireless device may send, to the first base station, an RRCconnection reestablishment/setup/resume request message for an RRCconnection reestablishment/setup/resume request. The RRC connectionreestablishment/setup/resume request message may comprise an indicationparameter indicating that the wireless device experienced a connectionfailure (e.g. RLF, HOF, reconfiguration failure, other failure, and/orthe like). The indication parameter may indicate a cause of the RRCconnection reestablishment/setup/resume request. The indicationparameter may indicate that the wireless device has a report associatedwith a connection failure to transmit to a base station (e.g. the firstbase station).

In an example, the wireless device may receive, from the first basestation, a UE information request message indicating a request totransmit a radio link failure (RLF) report to the first base station. Inan example, the wireless device may transmit, to the first base station,a first message. In an example, the first message may be transmitted inresponse to the UE information request message. In an example, the firstmessage may be an UE information response message (e.g.UEInformationResponse message). The first message may be an RRC message.In an example, the first message may comprise a radio link failure (RLF)report for the connection failure of the wireless device. The RLF reportmay be associated with the beam failure recovery request failure at thefirst cell of the base station.

In an example, the RLF report may comprise at least one of a cellidentifier of the first cell, and/or one or more elements of the beamconfiguration parameters received from the base station of the firstcell. In an example, the RLF report may comprise at least one of theCSI-RS beam indexes, the SS beam indexes, BRACH resource configurations,the BRACH preamble configuration parameters, the beam based SRStransmission configuration information, the beam based CSI-RSconfiguration parameters, the beam based SS configuration parameters,the beam failure recovery timer, the number of random access preambletransmission repetitions, the beam measurement configuration parameters,the beam failure detection RS resource configuration information (e.g.Beam-Failure-Detection-RS-ResourceConfig), candidate beam RS list (e.g.Candidate-Beam-RS-List) for radio link quality measurements on theserving cell, the beam failure candidate beam received power threshold(e.g. Beam-failure-candidate-beam-threshold), control resource set(CORESET) information for beam failure recovery response (e.g.Beam-failure-Recovery-Response-CORESET), the RACH resource for beamfailure recovery procedure (e.g.Beam-failure-recovery-request-RACH-Resource), the time windowinformation for beam failure recovery request (e.g.Beam-failure-recovery-request-window), the TCI-StatesPDCCH, and/or thelike. In an example, if the beam failure recovery request is indicatedby transmitting a PUCCH signal (e.g., via scheduling request resource onone or more cells, which may be at least one of the failed cell, aprimary cell, a PUCCH secondary cell, etc.) and/or by transmitting a MACCE (via one or more cells, which may be different from the failed cell),the RLF report may further comprise at least one of: a cell identifierof the cell via which the beam failure recovery request was transmitted,indicator of a PUCCH resource via which the beam failure recoveryrequest was transmitted, and/or the like.

In an example, the RLF report may comprise one or more beam indexes ofthe one or more first beams (e.g. at least one beam of the one or morebeams configured at the first cell) of the first cell. The one or morefirst beams have the beam failure and/or the beam failure recoveryfailure. The RLF report may comprise one or more recovery attempt beamindexes of one or more recovery attempt beams to which the wirelessdevice attempted the beam failure recovery procedure (e.g. target beamsfor beam recovery or beams employed to transmit random access preamblesfor the beam failure recovery procedure) in response to the beamfailure.

In an example, the RLF report may comprise one or more reportinformation elements (IEs) indicating information associated with theconnection failure of the wireless device. The one or more report IEsmay indicate at least one of: a failed cell identifier of the failedcell (e.g. the first cell), wherein the wireless device experienced theconnection failure at the failed cell; an RLF cause of the connectionfailure, wherein the RLF cause indicating at least one of a firstinformation element (IE) indicating the connection failure is caused bythe beam failure recovery request failure, a second information element(IE) indicating the connection failure is based on the expiration of thebeam failure recovery timer, a t310 expiry, a random access problem, aradio link control (RLC) maximum number of retransmissions, or t312expiry; a wireless device identifier of the wireless device at thefailed cell; a carrier frequency value of the failed cell; a first timevalue (e.g. timeConnFailure) indicating time that elapsed since a lasthandover initialization for the wireless device until the connectionfailure; a second time value (e.g. timeSinceFailure) indicating timethat elapsed since the connection failure (or an establishment failure);a connection failure type indicating whether the connection failure isdue to an RLF or a handover failure; a measurement result, themeasurement result comprising at least one of a reference signalreceived power result or a reference signal received quality; a qualityclassification indication 1 bearer indicating the connection failureoccurred while a bearer with QCI value equal to 1 was configured; aC-RNTI of the wireless device at the first cell; and/or the like.

In an example, the failed cell identifier of the failed cell (e.g. thefirst cell) may comprise a global cell identifier (e.g. NCGI, ECGI, CGI,and/or the like), a physical cell identifier (e.g. PCI), and/or thelike. In an example, the failed cell may be a primary cell of thewireless device when the connection failure (e.g. the beam failurerecovery request failure) occurred.

In an example, the RLF cause of the connection failure may indicate thata cause of determining the connection failure of the wireless devicecomprises at least one of a t310 expiry, a random access problem (e.g.failure), a radio link control (RLC) maximum number of retransmissions,t312 expiry, and/or the like. In an example the RLF cause may compriseat least one of the first information element (IE) indicating theconnection failure is caused by the beam failure recovery requestfailure, and/or the second information element (IE) indicating theconnection failure is based on the expiration of the beam failurerecovery timer.

In an example, the first IE may indicate that the connection failure isdetermined in response to determining the beam failure recovery requestfailure. The first IE may indicate a beam failure recovery requestfailure. In an example, the first IE may indicate that a connectionfailure was determined after the time duration of the connection failuretimer (e.g. T310 or other type of timer). The connection failure timermay start before the beam failure recovery request failure (e.g. whenreceiving one or more out-of-sync indication, or when receiving a beamfailure indication from a lower layer), or may start in response to thebeam failure recovery request failure.

In an example, the second IE may indicate that the connection failure isbased on the expiration of the beam failure recovery timer. Theexpiration may cause the determination of the beam failure recoveryrequest failure. The second IE may indicate a beam failure recoverytimer expiry.

In an example, the t310 expiry may indicate that a timer t310 of thewireless device expired at the failed cell when the connection failureoccurred. The timer t310 may start when the wireless device detectsphysical layer related problems (e.g. for a primary cell) (e.g. when thewireless device receives a certain number (e.g. N310) consecutiveout-of-sync indications from lower layers). In an example, the timert310 may stop: when the wireless device receives a certain number (e.g.N311) consecutive in-sync indications from lower layers (e.g. for aprimary cell); upon triggering a handover procedure; upon initiating anRRC connection reestablishment procedure; and/or the like. In anexample, at an expiry of the timer t310, if security is not activated,the wireless device may go to an RRC idle state. In an example, at anexpiry of the timer t310, if security is activated, the wireless devicemay initiate an RRC connection reestablishment procedure.

In an example, the t312 expiry may indicate that a timer t312 of thewireless device expired at the failed cell when the connection failureoccurred. The timer t312 may start upon triggering a measurement reportfor a measurement identity for which the timer t312 has been configured,while the timer t310 is running. In an example, the timer t312 may stop:upon receiving a certain number (e.g. N311) of consecutive in-syncindications from lower layers; upon triggering a handover procedure;upon initiating a connection re-establishment procedure; upon an expiryof the timer t310; and/or the like. In an example, at an expiry of thetimer t312, if security is not activated, the wireless device may go toan idle state. In an example, at an expiry of the timer t312, ifsecurity is activated, the wireless device may initiate an RRCconnection reestablishment procedure.

In an example, the random access problem (e.g. failure) may indicatethat the wireless device experienced one or more random access problems(e.g. random access failures) at the failed cell when the connectionfailure occurred. In an example, the RLC maximum number ofretransmissions may indicate that an RLC layer of the wireless devicetried a maximum number of packet retransmissions when connection failureoccurred.

In an example, the wireless device identifier of the wireless device maycomprise a C-RNTI at the failed cell (e.g. at the first cell), atemporary mobile subscriber identity (TMSI), an International MobileSubscriber Identity (IMSI), Globally Unique Temporary Identifier (GUTI),and/or the like. In an example, the carrier frequency value may indicatea carrier frequency value of the failed cell. In an example, the carrierfrequency value may comprise at least one of an EARFCN, an ARFCN, and/orthe like, for example with a maximum value of a maxEARFCN. In anexample, the carrier frequency value may be determined according to aband used when obtaining a concerned measurement results.

In an example, the measurement result may comprise at least one of areference signal received power result (RSRP) or a reference signalreceived quality (RSRQ) of at least one of the failed cell, a lastserving cell, one or more serving cells, one or more neighboring cellsof the failed cell, one or more secondary cells of the wireless devicewhen the failed cell was a primary cell, and/or the like. In an example,the wireless device may determine one or more elements of themeasurement result by measuring when (or before/after) the wirelessdevice experiences the connection failure. In an example, the qualityclassification indication 1 bearer (e.g. drb-EstablishedWithQCI-1) mayindicate that the connection failure occurred while a bearer with QCIvalue 1 was configured.

In an example, as shown in FIG. 18 , FIG. 19 , and/or FIG. 21 , the basestation (e.g. serving the first cell) may receive, from the first basestation, the RLF report and/or one or more elements (e.g. the RLF causeand/or the beam configuration parameters) of the RLF report via an Xninterface, via an X2 interface, via an Xx interface, and/or the like(e.g. a direct interface between the base station and the first basestation). In an example, as shown in FIG. 20 , the base station mayreceive, from the first base station, the RLF report and/or the one ormore elements (e.g. the RLF cause and/or the beam configurationparameters) of the RLF report via one or more core network entities(e.g. one or more AMFs, one or more MMEs, one or more SGSNs, one or moreGGSNs, and/or the like), employing logical direct interfaces between thebase station and the one or more core network entities and/or betweenthe first base station and the one or more core network entities (e.g.an NG interface, an N2 interface, an S1 interface, and/or the like). Inan example, as shown in FIG. 17 and/or FIG. 19 , if the base station isthe first base station, the base station may receive the RLF report viathe first message (directly) from the wireless device.

In an example, the first base station may determine at least one cellconfiguration parameter of one or more cells of the first base stationfor one or more wireless devices based on the RLF report. The one ormore cells may comprise the failed cell (e.g. the first cell) of thewireless device. In an example, the at least one cell configurationparameter may comprise at least one of: at least one beam configurationparameters; at least one transmission power configuration parameter; atleast one frequency configuration parameter; at least one beamformingconfiguration parameter; at least one physical control channelscheduling parameter; at least one antenna configuration parameter; atleast one cell selection or reselection configuration parameter for oneor more wireless devices; at least one system information; at least oneinterference control parameter; and/or the like.

In an example, the at least one beam configuration parameters may be forone or more wireless devices. The at least one beam configurationparameters may comprise one or more parameters indicating at least oneof: a plurality of beam indexes of a plurality of beams; a plurality ofSSB beam configurations; a plurality of CSI-RS beam configurations; aplurality of beam directions of a plurality of beams; a subcarrierspacing for a plurality of beams; a cyclic prefix; a number ofcontiguous PRBs; an index in the set of one or more DL beams and/or oneor more UL beams; a link between a DL beam and an UL beam from a set ofconfigured DL beams and UL beams; a DCI detection to a PDSCH receptiontiming value; a PDSCH reception to a HARQ-ACK transmission timing value;a DCI detection to a PUSCH transmission timing value; an offset of afirst PRB of a DL bandwidth or an UL bandwidth, respectively, relativeto a first PRB of a bandwidth; and/or the like.

The at least one beam configuration parameters may comprise one or moreparameters indication at least one of CSI-RS beam indexes, SS beamindexes, BRACH resource configurations, BRACH preamble configurationparameters, beam based SRS transmission configuration information, beambased CSI-RS configuration parameters, beam based SS configurationparameters, beam failure recovery timer, number of random accesspreamble transmission repetitions, beam measurement configurationparameters, beam failure detection RS resource configuration information(e.g. Beam-Failure-Detection-RS-ResourceConfig), candidate beam RS list(e.g. Candidate-Beam-RS-List) for radio link quality measurements on theserving cell, beam failure candidate beam received power threshold (e.g.Beam-failure-candidate-beam-threshold), control resource set (CORESET)information for beam failure recovery response (e.g.Beam-failure-Recovery-Response-CORESET), RACH resource for beam failurerecovery procedure (e.g. Beam-failure-recovery-request-RACH-Resource),time window information for beam failure recovery request (e.g.Beam-failure-recovery-request-window), TCI-StatesPDCCH, and/or the like.

In an example, if a wireless device experiences a connection failureduring a time that a first beam of a plurality of beams of a cell isemployed, a base station may reconfigure uplink/downlink transmissionpower for the first beam for one or more wireless devices.

In an example, if a channel quality (e.g. RSRP, RSRQ) of a second beamof a plurality of beams of a cell is good (e.g. better than a channelquality of an active BWP) when a wireless device experiences aconnection failure during a time that a first beam is employed, a basestation may make one or more wireless devices to employ the second beamwhen measurement results of the one or more wireless device are similarto measurement results of the wireless device at the connection failure.

In an example, the at least one transmission power configurationparameter may comprise a maximum downlink/uplink cell transmissionpower, a physical downlink control channel (PDCCH) transmission power,one or more power control parameters for uplink and/or downlink, a TPCconfiguration parameter, an SRS configuration parameter, and/or the likefor one or more wireless device and/or for the first base station. In anexample, if the base station determines that the connection failureoccurred because of a low transmission power of a PDCCH (e.g. based onthe measurement result of the RLF report), the first base station mayincrease a transmission power of the PDCCH. In an example, if theconnection failure occurred because of large interferences on a PDCCH,the first base station may reschedule the PDCCH to be located at othersubframes.

In an example, if a wireless device experiences a connection failureduring a time that a first beam is employed, a base station may increasean uplink/downlink power level (e.g. 0.1 dB increase) for one or morewireless devices (e.g. UEs served in the first cell) when the one ormore wireless devices employ the first beam.

In an example, if a cause of a connection failure of a wireless deviceis a random access problem and the wireless device experiences theconnection failure during a time that a first beam is employed, a basestation may not configure the first beam for a random access preambletransmission of one or more wireless devices.

In an example, if a cause of a connection failure of a wireless deviceis an RLC maximum number of retransmissions (e.g. uplink transmissionproblem; a number of RLC retransmissions is over a threshold value) andthe wireless device experiences the connection failure during a timethat a first beam is employed, a base station may increase an uplinkpower level for one or more wireless devices when the one or morewireless devices employ the first beam.

In an example, the at least one frequency configuration parameter maycomprise a carrier frequency, a bandwidth, one or more bandwidth partconfiguration parameters, and/or the like. In an example, if a cell ofthe base station experiences large interferences from neighboring cells,the base station may change an operation frequency to other frequency.In an example, if a certain beam of a served cell of the base stationexperiences large interferences from neighboring cells or othertechnologies, the base station may make one or more wireless devices toemploy a beam other than the certain beam when measurement results ofthe one or more wireless devices are similar to measurement results ofthe wireless device at the connection failure.

In an example, the at least one beamforming configuration parameter maycomprise one or more beamforming direction configuration parameters, oneor more beam sweeping configuration parameters, one or moresynchronization signal (SS)/reference signal (e.g. CSI-RS) configurationparameters, one or more beam recovery related parameters, one or moreBRACH parameter, one or more preamble configuration parameters for beamrecovery, one or more random access configuration parameters of one ormore beams, and/or the like. In an example, if the connection failureoccurred because of a random access failure or a failure of beamrecovery procedure (e.g. out-of-sync), the base station may reschedulerandom access resources and/or BRACH resources, and/or may reconfigurepreambles to reduce random access contentions.

In an example, the at least one physical control channel schedulingparameter may comprise a subframe pattern configuration parameter, ameasurement subframe pattern configuration parameter, a transmissiontype parameter indicating a localized transmission and/or distributedtransmission, a resource block assignment configuration parameter, aCSI-RS configuration parameter, and/or the like. In an example, the atleast one antenna configuration parameter may comprise default antennaconfiguration parameters, an antenna port configuration parameter, anumber of CRS antenna port parameter, and/or the like. In an example,the at least one cell selection or reselection configuration parameterfor one or more wireless devices may comprise one or more power/timethreshold parameters for cell selection/reselection of at least onewireless device of the base station, one or more cell priorityconfiguration parameters for cell selection/reselection, and/or thelike. In an example, the connection failure occurred because of a randomaccess failure of the wireless device, the base station may increasevalues of the one or more power/time threshold parameters to makewireless devices avoid the failed cell if the wireless devices do notsatisfy increased thresholds.

In an example, the base station may reconfigure one or more IEs of theat least one system information comprising at least one of systeminformation type block type 1 to 21 based on the RLF report. In anexample, the at least one interference control parameter may compriseone or more almost blank subframe configuration parameters, one or moreCoMP interference management related parameters, and/or the like. In anexample, if the connection failure occurred because of interferencesfrom a neighboring cell of the failed cell, the base station mayschedule resource blocks for the neighboring cell and the failed cellnot to use the resource blocks simultaneously.

In an example, the base station may transmit at least one systeminformation blocks comprising the at least one cell configurationparameter. The at least one system information blocks may be at leastone of the system information block type 1 to 21. The base station maytransmit at least one of the at least one cell configuration parameterto one or more wireless devices, e.g. via an RRC message. The one ormore wireless device may comprise the wireless device.

EXAMPLES

In an example, as shown in FIG. 22 , a wireless device may detect a beamfailure on one or more first beams of a first cell. In response todetecting the beam failure, the wireless device may start a beam failurerecovery timer, and/or transmit a random access preamble. The wirelessdevice may determine a beam failure recovery request failure in responseto expiration of the beam failure recovery timer. The wireless devicemay transmit, to a first base station, a first message comprising aradio link failure report associated with the beam failure recoveryrequest failure. The radio link failure report may comprise at least oneof a first information element indicating that a connection failure iscaused by the beam failure recovery request failure and/or a secondinformation element indicating that the connection failure is based onthe expiration of the beam failure recovery timer.

In an example, the one or more first beams may comprise at least one ofa synchronization signal block beam and/or a channel stateinformation-reference signal beam. The wireless device may transmit therandom access preamble via a beam random access resource associated withat least one of a synchronization signal block with a reference signalreceived power above a first power value (e.g. rsrp-ThresholdSSB) and/ora channel state information-reference signal with a reference signalreceived power above a second power value (e.g.csirs-dedicatedRACH-Threshold). In an example, the radio link failurereport may further indicate at least one of a cell identifier of thefirst cell and/or one or more first beam indexes of the one or morefirst beams. The base station of the first cell may determine one ormore cell configuration parameters of the first cell based on the radiolink failure report. In an example, as shown in FIG. 23 and/or FIG. 25 ,the base station of the first cell may receive, from the first basestation, the radio link failure report. In an example, as shown in FIG.24 , the base station of the first cell may be the first base station.The base station may determine one or more cell configuration parametersof the first cell based on the radio link failure report.

Embodiments may be configured to operate as needed. The disclosedmechanism may be performed when certain criteria are met, for example,in a wireless device, a base station, a radio environment, a network, acombination of the above, and/or the like. Example criteria may bebased, at least in part, on for example, wireless device or network nodeconfigurations, traffic load, initial system set up, packet sizes,traffic characteristics, a combination of the above, and/or the like.When the one or more criteria are met, various example embodiments maybe applied. Therefore, it may be possible to implement exampleembodiments that selectively implement disclosed protocols.

A base station may communicate with a mix of wireless devices. Wirelessdevices and/or base stations may support multiple technologies, and/ormultiple releases of the same technology. Wireless devices may have somespecific capability(ies) depending on wireless device category and/orcapability(ies). A base station may comprise multiple sectors. When thisdisclosure refers to a base station communicating with a plurality ofwireless devices, this disclosure may refer to a subset of the totalwireless devices in a coverage area. This disclosure may refer to, forexample, a plurality of wireless devices of a given LTE or 5G releasewith a given capability and in a given sector of the base station. Theplurality of wireless devices in this disclosure may refer to a selectedplurality of wireless devices, and/or a subset of total wireless devicesin a coverage area which perform according to disclosed methods, and/orthe like. There may be a plurality of base stations or a plurality ofwireless devices in a coverage area that may not comply with thedisclosed methods, for example, because those wireless devices or basestations perform based on older releases of LTE or 5G technology.

According to various embodiments, a device such as, for example, awireless device, off-network wireless device, a base station, and/or thelike, may comprise one or more processors and memory. The memory maystore instructions that, when executed by the one or more processors,cause the device to perform a series of actions. Embodiments of exampleactions are illustrated in the accompanying figures and specification.Features from various embodiments may be combined to create yet furtherembodiments.

FIG. 26 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2610, a wireless device may detect a beamfailure on at least one beam. The at least one beam may be of a firstcell. At 2630, a beam failure recovery procedure may be started inresponse to the beam failure (2620). The beam failure recovery proceduremay comprise transmitting a recovery request for a first beam. At 2640,a beam failure recovery timer for the beam failure recovery proceduremay be started. At 2660, the wireless device may determine a connectionfailure based on expiration of the beam failure recovery timer (2650).At 2670, the wireless device may transmit a radio link failure report toa first base station based on the connection failure. The radio linkfailure report may comprise an index of the first beam.

According to an example embodiment, the wireless device may receive aradio resource control message. The radio resource control message maycomprise a random access preamble for the first beam. The transmittingof the recovery request may comprise transmitting the random accesspreamble. According to an example embodiment, the radio resource controlmessage may comprise at least one configuration parameter of a referencesignal for the first beam.

According to an example embodiment, the expiration of the beam failurerecovery timer may indicate a failure of the beam failure recoveryprocedure. According to an example embodiment, the radio link failurereport may comprise a time value for the beam failure recovery timer.

According to an example embodiment, the radio link failure report maycomprise a random access resource configuration parameter for therecovery request. According to an example embodiment, the radio linkfailure report may comprise a random access preamble configurationparameter for the recovery request. According to an example embodiment,the radio link failure report may comprise a number of random accesspreamble transmission repetitions. According to an example embodiment,the radio link failure report may comprise control resource setinformation for a beam failure recovery response. According to anexample embodiment, the radio link failure report further may compriseat least one beam index of the at least one beam of the first cell.According to an example embodiment, the radio link failure reportfurther may comprise a beam index of a candidate beam. According to anexample embodiment, the radio link failure report further may comprise areceived power value for a candidate beam for the beam failure recoveryprocedure.

According to an example embodiment, the wireless device may receive beamconfiguration parameters. The radio link failure report may comprise thebeam configuration parameters. According to an example embodiment, theat least one beam may comprise a synchronization signal block beam.According to an example embodiment, the at least one beam may comprise achannel state information-reference signal beam.

According to an example embodiment, the wireless device may transmit therecovery request of the beam failure recovery procedure via a randomaccess resource for a synchronization signal block with a referencesignal received power being equal to or larger than a first power value.According to an example embodiment, the wireless device may transmit therecovery request of the beam failure recovery procedure via a randomaccess resource for a channel state information-reference signal with areference signal received power being equal to or larger than a secondpower value.

According to an example embodiment, the radio link failure report maycomprises a field indicating that a failure of the beam failure recoveryprocedure is a cause of the connection failure. According to an exampleembodiment, the radio link failure report further comprises a fieldindicating that the expiration of the beam failure recovery timer is acause of the connection failure. According to an example embodiment, theradio link failure report may comprise a cell identifier of the firstcell. According to an example embodiment, the radio link failure reportmay comprise at least one beam index of the at least one beam. Accordingto an example embodiment, the radio link failure report may comprise anidentifier of the wireless device at the first cell. According to anexample embodiment, the radio link failure report may comprise a fieldindicating a carrier frequency of the first cell. According to anexample embodiment, the radio link failure report may comprise a timevalue indicating a time duration that elapsed since a last handoverinitialization for the wireless device until the connection failure.According to an example embodiment, the radio link failure report maycomprise a time value indicating a time duration that elapsed since theconnection failure. According to an example embodiment, the radio linkfailure report may comprise a reference signal received power value ofthe first cell. According to an example embodiment, the radio linkfailure report may comprise a reference signal received quality value ofthe first cell.

According to an example embodiment, a second base station serving thefirst cell from the first base station, may receive at least a part ofthe radio link failure report. According to an example embodiment, thesecond base station may determine, based on the at least a part of theradio link failure report, configuration parameters of the first cell.According to an example embodiment, the second base station may transmitthe configuration parameters to one or more wireless devices. Accordingto an example embodiment, the configuration parameters may comprise beamconfiguration parameters. According to an example embodiment, the secondbase station may receive at least a part of the radio link failurereport from the first base station via at least one core network node.

According to an example embodiment, the first base station may serve thefirst cell. According to an example embodiment, the wireless device mayselect, based on the determining the connection failure, a second cell.According to an example embodiment, the first base station may transmita preamble for a random access to the second cell of the first basestation. According to an example embodiment, a random access responsemay be received in response to the preamble for the random access.According to an example embodiment, the first cell may be the secondcell. According to an example embodiment, the configuration parametersof the first cell may be based on at least a part of the radio linkfailure report. According to an example embodiment, the first cell maybe a primary cell of the wireless device. According to an exampleembodiment, the wireless device may transmit to the first base station,a radio resource control message indicating the connection failure.According to an example embodiment, an information request message forinformation of the connection failure may be received. According to anexample embodiment, the transmitting of the radio link failure reportmay be based on the information request message.

FIG. 27 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2710, a wireless device may detect a beamfailure on at least one beam. The at least one beam may be of a firstcell. At 2730, a beam failure recovery procedure may be started inresponse to the beam failure (2720). The beam failure recovery proceduremay comprise transmitting a recovery request for a first beam. At 2740,a beam failure recovery timer for the beam failure recovery proceduremay be started. At 2760, the wireless device may determine a connectionfailure based on expiration of the beam failure recovery timer (2750).At 2770, the wireless device may transmit a radio link failure report toa first base station based on the connection failure. The radio linkfailure report may comprise a field indicating that the expiration ofthe beam failure recovery timer is a cause of the connection failure.

FIG. 28 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2810, a wireless device may detect a beamfailure on at least one beam. The at least one beam may be of a firstcell. At 2830, a beam failure recovery procedure may be started inresponse to the beam failure (2820). The beam failure recovery proceduremay comprise transmitting a recovery request for a first beam. At 2840,a beam failure recovery timer for the beam failure recovery proceduremay be started. At 2860, the wireless device may determine a connectionfailure based on expiration of the beam failure recovery timer (2850).At 2870, the wireless device may transmit a radio link failure report toa first base station based on the connection failure. The radio linkfailure report may comprise a field indicating that a failure of thebeam failure recovery procedure is a cause of the connection failure.According to an example embodiment, the wireless device may determine,response to the expiration of the beam failure recovery timer, thefailure of the beam failure recovery procedure.

FIG. 29 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 2910, a wireless device may detect a beamfailure on a first cell. At 2930, a beam failure recovery procedure maybe started in response to the beam failure (2920). The beam failurerecovery procedure may comprise transmitting a recovery request for afirst beam. At 2940, a beam failure recovery timer for the beam failurerecovery procedure may be started. At 2960, the wireless device maydetermine a connection failure based on expiration of the beam failurerecovery timer (2950). At 2970, the wireless device may transmit, basedon the connection failure, a radio link failure report. The radio linkfailure report may comprise an index of the first beam.

FIG. 30 is an example flow diagram as per an aspect of an embodiment ofthe present disclosure. At 3010, a wireless device may detect a beamfailure on a first cell. At 3030, a beam failure recovery procedure maybe started in response to the beam failure (3020). The beam failurerecovery procedure may comprise transmitting a recovery request for afirst beam. At 3040, a connection failure may be determined, based onfailure of the beam failure recovery procedure. At 3050, the wirelessdevice may transmit, based on the connection failure, a radio linkfailure report. The radio link failure report may comprise an index ofthe first beam.

In this disclosure, “a” and “an” and similar phrases are to beinterpreted as “at least one” and “one or more.” Similarly, any termthat ends with the suffix “(s)” is to be interpreted as “at least one”and “one or more.” In this disclosure, the term “may” is to beinterpreted as “may, for example.” In other words, the term “may” isindicative that the phrase following the term “may” is an example of oneof a multitude of suitable possibilities that may, or may not, beemployed to one or more of the various embodiments.

If A and B are sets and every element of A is also an element of B, A iscalled a subset of B. In this specification, only non-empty sets andsubsets are considered. For example, possible subsets of B={cell1,cell2} are: {cell1},{cell2}, and {cell1, cell2}. The phrase “based on”(or equally “based at least on”) is indicative that the phrase followingthe term “based on” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “in response to” (or equally “inresponse at least to”) is indicative that the phrase following thephrase “in response to” is an example of one of a multitude of suitablepossibilities that may, or may not, be employed to one or more of thevarious embodiments. The phrase “depending on” (or equally “depending atleast to”) is indicative that the phrase following the phrase “dependingon” is an example of one of a multitude of suitable possibilities thatmay, or may not, be employed to one or more of the various embodiments.The phrase “employing/using” (or equally “employing/using at least”) isindicative that the phrase following the phrase “employing/using” is anexample of one of a multitude of suitable possibilities that may, or maynot, be employed to one or more of the various embodiments.

The term configured may relate to the capacity of a device whether thedevice is in an operational or non-operational state. Configured mayalso refer to specific settings in a device that effect the operationalcharacteristics of the device whether the device is in an operational ornon-operational state. In other words, the hardware, software, firmware,registers, memory values, and/or the like may be “configured” within adevice, whether the device is in an operational or nonoperational state,to provide the device with specific characteristics. Terms such as “acontrol message to cause in a device” may mean that a control messagehas parameters that may be used to configure specific characteristics ormay be used to implement certain actions in the device, whether thedevice is in an operational or non-operational state

In this disclosure, various embodiments are disclosed. Limitations,features, and/or elements from the disclosed example embodiments may becombined to create further embodiments within the scope of thedisclosure.

In this disclosure, parameters (or equally called, fields, orInformation elements: IEs) may comprise one or more information objects,and an information object may comprise one or more other objects. Forexample, if parameter (IE) N comprises parameter (IE) M, and parameter(IE) M comprises parameter (IE) K, and parameter (IE) K comprisesparameter (information element) J. Then, for example, N comprises K, andN comprises J. In an example embodiment, when one or more messagescomprise a plurality of parameters, it implies that a parameter in theplurality of parameters is in at least one of the one or more messages,but does not have to be in each of the one or more messages.

Furthermore, many features presented above are described as beingoptional through the use of “may” or the use of parentheses. For thesake of brevity and legibility, the present disclosure does notexplicitly recite each and every permutation that may be obtained bychoosing from the set of optional features. However, the presentdisclosure is to be interpreted as explicitly disclosing all suchpermutations. For example, a system described as having three optionalfeatures may be embodied in seven different ways, namely with just oneof the three possible features, with any two of the three possiblefeatures or with all three of the three possible features.

Many of the elements described in the disclosed embodiments may beimplemented as modules. A module is defined here as an element thatperforms a defined function and has a defined interface to otherelements. The modules described in this disclosure may be implemented inhardware, software in combination with hardware, firmware, wetware (i.e.hardware with a biological element) or a combination thereof, all ofwhich may be behaviorally equivalent. For example, modules may beimplemented as a software routine written in a computer languageconfigured to be executed by a hardware machine (such as C, C++,Fortran, Java, Basic, Matlab or the like) or a modeling/simulationprogram such as Simulink, Stateflow, GNU Octave, or LabVIEWMathScript.Additionally, it may be possible to implement modules using physicalhardware that incorporates discrete or programmable analog, digitaland/or quantum hardware. Examples of programmable hardware comprise:computers, microcontrollers, microprocessors, application-specificintegrated circuits (ASICs); field programmable gate arrays (FPGAs); andcomplex programmable logic devices (CPLDs). Computers, microcontrollersand microprocessors are programmed using languages such as assembly, C,C++ or the like. FPGAs, ASICs and CPLDs are often programmed usinghardware description languages (HDL) such as VHSIC hardware descriptionlanguage (VHDL) or Verilog that configure connections between internalhardware modules with lesser functionality on a programmable device. Theabove mentioned technologies are often used in combination to achievethe result of a functional module.

The disclosure of this patent document incorporates material which issubject to copyright protection. The copyright owner has no objection tothe facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the Patent and Trademark Officepatent file or records, for the limited purposes required by law, butotherwise reserves all copyright rights whatsoever.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example, and notlimitation. It will be apparent to persons skilled in the relevantart(s) that various changes in form and detail can be made thereinwithout departing from the scope. In fact, after reading the abovedescription, it will be apparent to one skilled in the relevant art(s)how to implement alternative embodiments. Thus, the present embodimentsshould not be limited by any of the above described exemplaryembodiments.

In addition, it should be understood that any figures which highlightthe functionality and advantages, are presented for example purposesonly. The disclosed architecture is sufficiently flexible andconfigurable, such that it may be utilized in ways other than thatshown. For example, the actions listed in any flowchart may bere-ordered or only optionally used in some embodiments.

Further, the purpose of the Abstract of the Disclosure is to enable theU.S. Patent and Trademark Office and the public generally, andespecially the scientists, engineers and practitioners in the art whoare not familiar with patent or legal terms or phraseology, to determinequickly from a cursory inspection the nature and essence of thetechnical disclosure of the application. The Abstract of the Disclosureis not intended to be limiting as to the scope in any way.

Finally, it is the applicant's intent that only claims that include theexpress language “means for” or “step for” be interpreted under 35U.S.C. 112. Claims that do not expressly include the phrase “means for”or “step for” are not to be interpreted under 35 U.S.C. 112.

What is claimed is:
 1. A method comprising: initiating, by a wirelessdevice, a beam failure recovery procedure based on a beam failure of atleast one beam of a cell; determining a radio link failure based on afailure of the beam failure recovery procedure; and transmitting a radiolink failure report comprising: a first field indicating that thefailure of the beam failure recovery procedure is a cause of the radiolink failure; and a second field indicating a random access resource forthe beam failure recovery procedure.
 2. The method of claim 1, furthercomprising receiving a radio resource control message comprising one ormore beam configuration parameters of the at least one beam of the cell.3. The method of claim 2, wherein: the radio resource control messageindicates a random access preamble for the beam failure recoveryprocedure; and the beam failure recovery procedure comprisestransmitting the random access preamble for a recovery request.
 4. Themethod of claim 2, wherein the radio link failure report comprises theone or more beam configuration parameters of the at least one beam ofthe cell.
 5. The method of claim 1, wherein the radio link failurereport comprises at least one of: control resource set information forthe beam failure recovery procedure; or a number of random accesspreamble transmissions associated with the beam failure recoveryprocedure.
 6. The method of claim 1, wherein the radio link failurereport indicates at least one of: a cell identifier of the cell; atleast one beam index of the at least one beam of the cell; a beam indexof a candidate beam for the beam failure recovery procedure; or areceived power for the candidate beam for the beam failure recoveryprocedure.
 7. The method of claim 1, wherein the at least one beamcomprises at least one of: a synchronization signal block beam; or achannel state information-reference signal beam.
 8. The method of claim1, further comprising: selecting, by the wireless device and based onthe determining the radio link failure, a second cell of a first basestation; transmitting, to the first base station, a preamble for arandom access to the second cell of the first base station; andreceiving a random access response in response to the preamble for therandom access.
 9. A wireless device comprising: one or more processors;and memory storing instructions that, when executed by the one or moreprocessors, cause the wireless device to: initiate a beam failurerecovery procedure based on a beam failure of at least one beam of acell; determine a radio link failure based on a failure of the beamfailure recovery procedure; and transmit a radio link failure reportcomprising: a first field indicating that the failure of the beamfailure recovery procedure is a cause of the radio link failure; and asecond field indicating a random access resource for the beam failurerecovery procedure.
 10. The wireless device of claim 9, wherein theinstructions, when executed by the one or more processors, further causethe wireless device to receive a radio resource control messagecomprising one or more beam configuration parameters of the at least onebeam of the cell.
 11. The wireless device of claim 10, wherein: theradio resource control message indicates a random access preamble forthe beam failure recovery procedure; and the beam failure recoveryprocedure comprises transmitting the random access preamble for arecovery request.
 12. The wireless device of claim 10, wherein the radiolink failure report comprises the one or more beam configurationparameters of the at least one beam of the cell.
 13. The wireless deviceof claim 9, wherein the radio link failure report comprises at least oneof: control resource set information for the beam failure recoveryprocedure; or a number of random access preamble transmissionsassociated with the beam failure recovery procedure.
 14. The wirelessdevice of claim 9, wherein the radio link failure report indicates atleast one of: a cell identifier of the cell; at least one beam index ofthe at least one beam of the cell; a beam index of a candidate beam forthe beam failure recovery procedure; or a received power for thecandidate beam for the beam failure recovery procedure.
 15. The wirelessdevice of claim 9, wherein the at least one beam comprises at least oneof: a synchronization signal block beam; or a channel stateinformation-reference signal beam.
 16. The wireless device of claim 9,wherein the instructions, when executed by the one or more processors,further cause the wireless device to: select, based on the wirelessdevice determining the radio link failure, a second cell of a first basestation; transmit, to the first base station, a preamble for a randomaccess to the second cell of the first base station; and receive arandom access response in response to the preamble for the randomaccess.
 17. A first base station comprising: one or more processors; andmemory storing instructions that, when executed by the one or moreprocessors, cause the first base station to: receive a radio linkfailure report comprising: a first field indicating that a failure of abeam failure recovery procedure is a cause of a radio link failure; anda second field indicating a random access resource for the beam failurerecovery procedure.
 18. The first base station of claim 17, wherein theinstructions, when executed by the one or more processors, further causethe first base station to: receive, from a second base station, a partof the radio link failure report; determine, based on the part of theradio link failure report, configuration parameters of a cell on which abeam failure occurred; and transmit, to one or more wireless devices,the configuration parameters.
 19. The first base station of claim 17,wherein the instructions, when executed by the one or more processors,further cause the first base station to transmit a radio resourcecontrol message comprising one or more beam configuration parameters ofat least one beam of a cell for which the beam failure recoveryprocedure is performed.
 20. The first base station of claim 19, wherein:the radio resource control message indicates a random access preamblefor the beam failure recovery procedure; and the beam failure recoveryprocedure comprises receiving the random access preamble for a recoveryrequest.